It depends upon the processor your wanting to work with, but generally the PICs have a roughly standard ASM instruction set for all their microcontrollers. This tutorial is specifically over the 16F84 PIC:
http://www.mstracey.btinternet.co.uk/pictutorial/picmain.htmJust Google search the part number of your PIC chip and assembly, to find the specific instruction set it has to offer.
Just as an FYI, unless you need the PIC chip your working with to be ultra-time critical, then I suggest you stick with C. ASM after a while drains your focus, believe me I've programmed with the 65816C Chip(The one used in the Super NES) and it's Assembly is a mental ordeal
, but then again it was a microprocessor not a microcontroller(Having to address external chips vs all-in-one hardware registers for a microcontroller)
So its up to you whether or not to go with ASM or stick with C.
Hope this helps
,macdad-(Nick)