C, A Software Engineering Approach by Peter Darnell and Philip Margolis
This was the very first programming book I ever purchased, and remains to be one of my favorites. The book covers just about every aspect of C, as well as stylistic guidelines, project planning recommendations, optimization tips, and more, and contains many useful appendixes, including a mini C library reference. It even includes the full source code for a lexical scanner for C, which is very cool. Clear and concise, this compact little book is an extremely practical guide to programming in C.
I highly recommend this book.