Images for Games

I have an idea to build a blackberry game based on some tech I recently implemented on another project. It uses SVG to create interactive web pages that work on Blackberries, mobile phones... pretty much everything except things like the iphone. (no comment)

So the problem is where do i go to get graphics for characters. I need space ships, aliens, space marines that kind of thing. But I have no idea where to look. Anybody have any ideas? Anybody want to help? Obviously I can't draw and have no budget yet so professional help is probably out of the question.