Honestly, drawing with a mouse is never easy. It's a pain in the neck. I have a friend who claims a trackball is better for drawing, but I've never seen it.
You CAN get a graphics tablet. They have some for about $35-40 now, and you use a stylus to draw on a flat surface, which transfers to the computer.
Here are some examples.
http://www.tigerdirect.com/applications/SearchTools/search.asp?keywords=tablet&searchbtn.x=0&searchbtn.y=0