I simply wanted to find out a little bit more about what parts of structuralism, post-structuralism and deconstruction you were interested in - any particular philosophers such as Derrida or Foucault, for example?
Anyway, describing such phenomena is in itself a philosophical activity - with this area you'll find there is a lot of 'tail eating' (putting a question mark against the very assumptions you are making in an argument), but here goes.
Structuralism arose on the continent, in particular in France, in the early 60s. The first "big name" was Claude Levi-Stauss, an anthropologist, who took on Jean-Paul Sartre, the leading French intellectual and philosopher of the time, and didn't so much win, as went unanswered (which from Sartre's point of view was worse). Here was France's main philosopher, Sartre, with something to say about everything, attacked in Levi-Strauss' The Savage Mind, and yet who didn't reply! The implication was that he couldn't reply, and the intellectual mood began to move towards Levi-Strauss' intellectual position, which he called Structuralism.
A simple explanation of structuralism is that it understands phenomena using the metaphor of language. That is, we understand language as a system, which defines itself in terms of itself. There is no language 'behind' language with which we understand it, no meta-language to explain what language means. Instead it is a self-referential system. Words explain words explain words (e.g. a dictionary).
Such an approach was an attack on other types of philosophy which see some phenomena as prior to other phenomena, or believe there is a "core" of truth which is "reality", which is behind the world of "appearance". For example Marxists might argue that we can understand the world ("appearance") by examining the relations of production ("reality"), or some fundamentalist Christians might argue that we should understand the world as a battle of God against Satan, so this "truth" is hidden, but in fact it explains the world.
Some other Structuralists are Roland Barthes, who claimed the term for a while, who was a literary critic and wrote about the "Death of the Author" (he argued the author could not claim to know what his/her book was about, or could not know the "Truth" about the book, any more than any reader could know - he challenged the idea that the author had some hidden Truth about the book); Michel Foucault, who was a historian and argued that science has to be understood socially before it can be understood intellectually - for example he showed how "madness" is primarily a social invention, rather than a medical discovery; and Jacques Lacan, a psychoanalyst who claimed the unconscious is structured like a language.
So we can see that a primary feature of the Structuralists is their attack on "foundationalism", any thought that claims to have found a Firm Foundation on which we can construct beliefs. Instead they emphasise the "relatedness" of truth, how Truth is not something we 'discover', or can 'own', or can 'start from', but instead an effect, a movement or perhaps even a style.
Moving on from the Structuralists we some to Derrida and Deconstruction. I come to Derrida next since his first three important books were published in 1967, which is ahead of the main Post-Structuralist book Anti-Oedipus which came out in the early 1970s.
Derrida can be called a Post-Structuralist in a sense, since he moves on from Structuralism, taking some of it for granted, and challenging other parts of it. Where the Structuralists constructed a system, a structure, Derrida deconstructs it, that is, he takes it apart. However, the disconcerting thing is that he does so from the inside. His technique of deconstruction shows how structures or systems of thought contain the seeds of their own downfall.
Derrida does not have a system of thought as such, instead he simply reads an author, for example Rousseau or Levi-Strauss or Hegel, and shows how their thought contains contradictions. And further, these contradictions are not something which can be corrected, as if the author had errors in an argument which, once corrected, could produce a better argument, no - rather the contradictions were conditions of the system of thought existing in the first place!
Each system of thought Derrida shows to be necessarily contradictory. How he does this is quite technical, but the idea is to show how the system (1) creates binary pairs - for example good and bad, male and female, black and white, writing and speaking, mad and sane etc; (2) prioritises one term over another, and indeed defines one in terms of the other - for example male over female (what Derrida calls 'Phallocentrism'), sane over mad, good over bad etc. (3) then show that in fact you may as well prioritise the second term over the first - show how the first term is dependent on the second, (4) finally show how the system is dependent on this marginalising of the second term, when in fact it relies on the second term (the marginal) also, in some sense, being at the centre.
Post-Structuralism's main book, Anti-Oedipus by Deleuze and Guattari is in fact an attempt to combine Marx and Freud (the subtitle is 'Capitalism and Schizophrenia') by liberation through free desire. Post-Structuralism is really a cultural movement more than an intellectual movement. Structuralism in the 60s was at least in part an intellectual programme, and it was possible to analyse phenomena by treating them as a system. Post-Structuralism moved beyond this, questioning the notions of Truth, Reality, Meaning, Sincerity, Good etc. It regarded all absolutes as constructions, truth was created, it was an effect, it wasn't present 'in' something. Similarly there was no authority, no Real, everything was defined in terms of everything else, and that process itself was relative and constructed.
The main philosopher for the post-structuralists was Nietzsche, whose main thought began with the realisation that if God is dead, anything is possible - everything is permitted, everything is relative. There are no absolutes anymore. Nietzsche also wrote is a style similar to an Old Testament prophet (see for example his Thus Spoke Zarathustra) - his style is full of such phrases as "we are living among the ruins of God" - and Post-Structuralists tend to follow this poetic style.
As this movement was growing in popularity in the 70s some other important things were happening. The radical political groups from the 60s (for example the Maoists) were coming to an ideological dead-end; Solzhenitsyn was being translated, and revealing in detail the horrors of Eastern Europe; the importance of the media and media saturation of life was becoming an important cultural phenomena. These now mixed with the philosophical currents just described with the following effects.
Firstly, there was a large backlash against Marxism and socialism. It was argued that Marxism was a "totalizing" system, whose intellectual totalitarianism moved necessarily to the Gulag, and instead liberalism and capitalism were embraced as being more open and relative. Secondly there was a move of intellectuals away from political engagement (Sartre for example had always been out marching with the students, and Foucault was often in demonstrations for prison rights, amongst other things), and back to "intellectual" work. Finally there was the emphasis on the media in defining reality for us, and an analysis of society as "postmodern" (fragmentary, full of images, saturated by the media, making everything relative, ephemeral and short-lived).
Following these consequences there are now a number of criticisms of post-structuralism and deconstruction as providing the philosophical justification for conservatism, reaction, de-politicising society and leading to an irresponsible, hedonistic lifestyle (for example, did Foucault still have unsafe sex when he knew he had aids? should Derrida have tried to defend Paul de Man's Nazi record? What of Heidegger's Nazi past? What of Baudrillard's claim that the Gulf War never happened?) In response to these criticisms, some excesses of post-structuralism and deconstruction are now over, and currently there appears to be a more sober mood to try to re-position these intellectual movements within the fight for human rights, and to create better human values.
Books:
Structuralism and Since John Sturrock (ed)
Introduction to various intellectuals such as Derrida, Foucault, Barthes etc.
Against Postmodernism Alex Callinicos
Marxist criticism of structuralism, deconstruction and poststructuralism - clearly written and well argued.
The Transparency of Evil Jean Baudrillard
Baudrillard is the postmodern author, writing about how the media has taken over.
Deconstruction Christopher Norris
Norris is a critical supporter of deconstruction, generally in favour of it - or at least in favour of what it is capable of - but his book on Baudrillard and the Gulf War shows that he is certainly against its excesses.
Contingency and Irony Richard Rorty
Rorty is an American liberal who takes arguments from Derrida and others and uses them to defend his 'relativist' views - very readable and enjoyable.