The Flaxseed Pathfinder Lodge - where you can find a TON of resources about playing Pathfinder Society games in a Play-by-Post format!
I STRONGLY advise newer players to Play-by-Post gaming to check out the amazing resources that The Flaxseed Lodge has put together. In fact, rather than re-post all of the links that are there, I'll just add a few beyond the ones already referenced above:
How to create a PFS character for PbP - Good basic info!
DH's Guide to PbP - Especially his "advanced" tricks!
PFS Session Tracker - A fantastic online database for you to keep track of what you've already played and GM'd. I use this myself and highly recommend it!
