PIC C is pretty simple to cope with - if you can program a PIC (or any other uProcessor) it isn't difficult to pick up. Of course, knowing C as well would certainly help!
The first place to start (as always) if
Google[
^] - there are a collection of tutorials here.
We can't really help with the specifics - we don't have access to your hardware designs or even know which of the pretty large PIC range you are looking at.