Sorry for the late reply.
Every microprocessor (and microcontroller) has an instruction set which is called assembly language, you can program any PIC in assembly language but not all can be programmed in C. When you compile C code, it will spit out an assembly listing of that code.
Unfortunately I don't have any C specific tutorials and I don't plan on making any, anytime soon. You are correct though, C is a great language to use when working with microcontrollers. Have you considered Basic? I have found it to be a fantastic language and quite similar to C in a lot of ways. I actually prefer to program microcontrollers in Basic rather than C. I do have a section of the forum that deals with Basic programming.
If you did want a C tutorial, you could try best microcontroller projects (I cant remember the exact website)
If you have a PICKIT 2 then you have all you need to program your PIC. Here is a fantastic post that will help you (thanks bitfogav!)http://www.bradsprojects.com/forum/viewtopic.php?f=9&t=484&p=2778&hilit=pickit#p2778
What do you mean exactly about the circuit elements?