You're on the right track. That book is considered a sort of standard to learning C programming by many (the first edition was the defacto C standard prior to the ANSI standard coming out and the 2nd edition of the book being released). Also, getting a handle on the language prior to actually taking a course, imo, is very smart, and will help you get through any courses on C by allowing you to focus on more important aspects of the language.

For now, I would recommend you keep up with exercises in the book, google for college/university level assignments and practice them. What you could also do is stick around these forums and see if you can do some of the homework assignments that invariably get posted here. Lastly, turn up the warning level of your compiler to the maximum. Many C compilers allow you to get away with doing things that are not allowed by the C standard, and you may end up learning very bad habits that will cause weird bugs, and much lost time. By learning how to write proper code early, you'll save yourself a lot of trouble.

Welcome to cboard, and enjoy your stay.