I writing a report on FSAA for a school project, and I remembered that some of the veterans in here have written some articles about FSAA, I believe. If you can supply me with some good material, I'll be very thankful.
Try the whitepapers from nVidia, 3dlabs and ATI. Most of the articles are refering to those pages since lot's of usefull information is provided by those companies.
I remember a very large and deep article written by fullon3D but the site has moved. Also a search on google will give you a good help.
Theres a beyond3d one about nvidias first AA. I'm sure there used to be one about the v5s FSAA too (back when beyond3d was all blue ) but that seems to have got lost.
[link=http://firingsquad.gamers.com/]FiringSquad[/link] did a write-up on how true multisampling works... you'll have to find it yourself, though, cos FS is blocked by my school's proxy
FWIW here are a few examples of differing sample patterns (down sampled with a simple box filter) that I produced a while ago to compare consumer 3D systems.