K&R is a great book however I feel there are better books these days. My two personal recommendations are C Programming A Modern Approach by K N King (2nd edition) and Programming in C by Kochan.

However the exercises in K&R are excellent so make sure you do them all. Actually the cost of K&R is justified just for the exercises IMHO.

Also get Understanding and Using C Pointers by Richard Reese, it is a must have.

Two other books I very much enjoyed are Head First C and 21st Century C (2nd edition). Head First has some nice "extra" bits like threads and networking in C. 21st Century C explains sensible, modern ways to do things in C and, more importantly, things you should NEVER do in C!