anything about that size is a good starter bike...
my friend got a kawasaki ninja 500r for his first bike, awesome starter bike and can be found dirt cheap. His was a 2000 with 8k on it, got it for 2600 from a dealer. Decently quick, decent handling, and dirt cheap insurance.
do you have your lisence or just your permit? I finally broke down after riding for almost 5 years on my permit and am in the middle of taking the MSF course. Its very simple, but it helps with your technique for the stupid stuff that you would forget about or never learn if no one really taught you how to ride right. Also you get your lisence at the end which is nice not having to go to the DMV, and best of all its FREE!!!