I am sure this question has been asked before. I might buy a new
300d. Wanted to know if I should get the kit lens or another. If
another which should I get.
What do you want to shoot? Without knowing that, I suggest the
105mm f2.8 macro, because it's such a great lens.
Think seriously about buying the kit lens (or the 18-125), and
buying lots of memory instead. If you get a cheap generic extra
battery and a 2GB memory card you'll be able to take a lot more
photos, which will help you learn more and make informed choices
about extra lenses.
For many purposes, you might be better off with the new Sigma
18-125mm zoom, because it gives you a little more zoom range
for a few extra dollars. But if you're lilkely to want better lenses
soon, buy the kit lens because it's so cheap. If you have dollars
to burn, I suggest the Sigma 12-24, the 24-70L and the 70-200IS
would give you excellent coverage over a good range. For only about
$US4000 too.
Read the forum, consider things like the Sigma 70-300 APO macro II,
the 17-40L and perhaps the 100-400IS. It's all about budget and what
you'll use the camera for.