Hey MD, this is totally off-topic, but I picked up Stephen Kochan's Objective C book on your recommendation. I like his approach of teaching C and Obj C as a single, integrated language. I still think Hillegass' book is unbeatable as an introduction to Cocoa but the Kochan book makes a great complement.
I also picked up "C Programming, A Modern Approach" by K.N. King and I can't recommend it highly enough for anyone who wants to learn or brush up on C. It's an expensive book, but you can get a good discount from some of the Amazon stores.