The Official C Tutorial for CS301 and CS331
Some of the files presented in the C tutorial are also available.
There is a plethora of books on C, but the one I have found particulaly useful is the one by Paul Wang, "An Introduction to ANSI C on UNIX" (Wadsworth). It is on reserve in the library. Of course, for reference, the classic is the book by Kernighan and Ritchie "The ANSI C Programming Language" (Prentice Hall). Unfortunately, none of these seem to exist on the Web...
On the Web I found an interesing short tutorial at http://www.mattababy.org/~belmonte/Teaching/CCC/CrashCourseC.html and another at http://www-h.eng.cam.ac.uk/help/tpl/languages/C/teaching_C/teaching_C.htmlA list of C resources is at http://www.lysator.liu.se/c/c-www.html