C programming - beginner tutorials/books?

I know this isn't C, but perhaps you should introduce your friend to a book called "Thinking in C++". It's free, and is very informative.

Look for K&R's The C Programming Language.

Other than that, he could pick the language up by looking at some code and reading through some references on ANSI C, which are easy to find with Google. It might not hurt to learn SDL alongside it, and libsdl.org has some simple games that are usually written in a single C file (such as aliens, etc.), so that might be of some benefit.

I'd say either K&R or the free online teach yourself c++.