Couple of untested links...

[telophase]

I just found these, and haven't had a chance to look through/test them.

Art Tutorials Wiki

Artweaver, a freeware program apparently similar to a stripped-down Painter. (ETA: There's a gallery forum where people post works. The "First artweaver piece (nude)" is very nice and similar to Painter, and this thread has one guy's works from ConceptArt.org, plus a couple of posts where he explains which brushes and settings he used.)

Comments

[fuuringo.livejournal.com]

Thanks for the Artweaver tip! I've been trying to use Painter for years but it never works right. It' too confusing.... This program seem to have some lags and glitches but overall it has a nice feel. ^^

[yhlee.livejournal.com]

Alas that it is Windows-only. *g* Looks neat, though!

[jhubert.livejournal.com]

Well, I hope you like the wiki - I've put a lot of effort into it.

And don't hesitate to add your own links to it... ;)