The Atrocity Archives

anything by Charles Stross, the atrocity archive could be a good place to start: humor, computers and cosmic horrors, whats not to like ;) Another would be halting state but time have properly overrun it. He even have a interesting background as a programmer/tech writer/pharmacist, read it here: http://www.antipope.org/charlie/blog-static/2009/07/how_i_go... (http://www.antipope.org/charlie/blog-static/2009/07/how_i_got_here_in_the_end_my_n.html)

Oh, a little more Stross: the Laundry books, starting with The Atrocity Archives. The British Secret Service has a division which guards against Lovecraftian occult horrors --- and your narrator is one of its I.T. grunts.