Here is a thread on the Pelican board. It's actually for older 911's, but the concepts are similar. The post explains how to build a bearing puller similar to sir tools for less than $20 at Home Depot or Lowes. I did mine (911) using the procedure. It was very simple. Hope this helps.
http://forums.pelicanparts.com/porsche-911-technical-forum/179300-rear-wheel-bearing-removal.html