some good models for characters are
milkshape ($25 though, not bad) Milkshape can make good models of almost anything else too.
http://www.swissquake.ch/chumbalum-soft/ms3d/index.html
If you're making spaceships (like i currently am)
www.wings3d.com
(it's free, and It's open-source.)
Photo editors. hmmmmmmmmmm not really sure, about free ones.Don't know off the top of my head.
Those modelers I would recommend.What kind of models are you planning on making??
Clans of our Galaxy
A new space simulation coming in 2004 -yellow-
updates:20 new spaceship models