Welcome to A.org :-)
I've never used Amithlon so I cannot answer most of your questions, but...
Will it run my software, like DPaintIV, Opus Magellan,
Lightwave, Cinema4D , games, AMiga cover disk software, etc? (I have a huge investment in Amiga hardware and software).
Amithlon won't run software that bangs the custom chipset like DPaint.
What Amithlon websites can I check out?
www.amithlon.net - see the big problem now? :-(