You didn't check out any of the GBA developer sites I talked about did you?

Bruno (ok, I didn't actually mention the URLs before... )

Page listing ARM compiler stuff at devrs.com
www.devrs.com/gba/
www.gbadev.org

Now, these guys are into Gameboy Advance development. A lot of guys write only for Thumb, so you'll see a lot of discussion for that as well. I'm not sure if you will need any additional files for the SA1000 over what seems to be widely talked about and linked.

You also be surprised what you can find by typing stuff like "arm gcc windows" etc. into google.