Let's try to be helpful here...
-Instead of using the line tool, try creating an oval or circle around or just inside the image you want to trace (in a different layer, of course), then bend the shape to fit the outline of the image you wish to trace. You can continue bending the shape at smaller and smaller points untill you get something that looks nice. HINT: Use the line tool to intersect your shape, then bend the shape to achieve angles. You can then delete the line.
-Another tool you can use is the Pen Tool. It is a bit tough to get used to, but it makes drawing nice things withou a tablet very easy once you get the hang of it. I can't explain how to use it any better than you could learn by just trying it out. (It looks like an inkwell pen).
-Finally, with a little bit of patience and a steady hand, you can use the pencil tool. Always keep one hand on the Ctrl-Z and be ready to redraw a lot of lines, but this method will usually give you the best tracing results.
Don't let people discourage you from tracing. It is a viable way to learn how to draw independantly. After you've made a few things by tracing, you'll remember how to make them without using a reference.
Peace Out