i'm left-handed, but switched to mousing with the right several years ago (out of necessity).
now i can mouse with either hand, equally as well (but have grown comfortable with the right)
keep at it and you'll adapt.
re: trackball. i have one, hate it. find it puts stress on my hand (as opposed to my wrist), and is much harder to do small, detailed moves.
however...same advice for me. if i keep at it...
