However the topic is considered, the problem of language has never been simply one problem among others. But never as much at present has it invaded, as such, the global horizon of the most diverse researches and the most heterogeneous discourses, diverse and heterogeneous in their intention, method and ideology.

The devaluation of the word "language" itself, and how, in the very hold it has upon us, it betrays a loose vocabulary, the temptation of a cheap seduction, the passive yielding to fashion, the consciousness of the avant garde, in other words—ignorance—are evidences of this effort

You can find many links to Jacques Derrida here, or among the General Philosophy Sites. A bibliography is also available.

Derrida was a student of Michel Foucault's, whom he has written on; he has also written on Heidegger, Genet, Artaud, and Freud, among others. Derrida has even crept into the sf of Samuel R. Delany.