For me, brings back some old memories of becoming a self-taught programmer ;-). Beej's Guides[1] seem timeless. I remember how I learned C more from following these guides than by C tutorials. For anyone out there who is trying to learn C, my advise would be to attempt some systems programming rather than just following C introductory books that teach you the language but not its typical/most common use.
Another good book for beginner C programmers (on linux) that I remember learning a lot from was Advanced Linux programming[2] ...although this might be slightly dated now (should be good enough to start exploration tho')
My specialization was Systems and Network Programming and it was before this site, facebook or stack overflow existed. I remember it was really hard to find good materials on the internet. It took me 2 weeks to write remote file editor (server + client with GUI written in GTK) in pure C, having resources that are available freely today it would take a lot less time.
