The AFL Analytics community is wonderfully inclusive and supportive. If you are looking for discussions about AFL Analytics, I highly reccomend Twitter. There is a very active commnity there.
AFL Data
Most of the data I use comes from the following two websites
AFL Tables
Footy Wire
AFL Analytics
Below are some fantastic blogs that I could only dream to be. They create some amazing content week in week out.
Matter of Stats | Twitter
Analysis of AFL | Twitter
The Arc | Twitter
Squiggle
Hurling People Now | Twitter
The Graft | Twitter
Figuring Footy | Twitter
Footy Maths Institue | Twitter
Insight Lane | Twitter