I have also found plasmaspider and downloaded some of the dxf files that people have uploaded and am happy so far with what I've found.
Last week I stumbled onto Gary's E-bay site here,
http://www.signtorch.com/store/home.php
I called and talked with Gary for probably an hour, and then I downloaded some of his free samples and burned out the Steer head yesterday and was very pleased with how it came out. I only sized it to a 12" x 12" dimension and burned it out of 10 guage (apx 1/8" material, 40amps, 84 ipm, 75 psi. air.) for a trial and it burned out great, so I went ahead and ordered his Super Bundle. They said it shipped today so should get hear next week. Will be fun to have a few thousand images to play with I think.
The Eagle is from the free download that Jason emailed me last week from his website here.
http://www.customdxffiles.com/ It also burned out very nicely.
I am really new to this art stuff but so far it looks like it's gona be a lot of fun.