You should first figure out if you really want to learn C...
If your on a mac, and your goal is cross-platform, look at
REALbasicIf your on a PC, and your goal is cross-platform, look at Java.
If your on a mac, and your goal is mac, look at Cocoa.
If your on PC, and your goal is PC, look at (Go ahead and shot me) Visual Basic/.Net or Java. (Java.)
I really don't honestly understand why anybody would write in C, although I am considered a newb-ish programmer.
My summery: C is hard. I like Jello.