Need help decided on a bike.
 

Hello all,

I am new to the biking world and live in Portland, OR, so I need to get with the picture and get a bike, haha.

So I am commuting roughly 10 miles about 3 times a week. There are moderate up and down hills.

I am thinking about purchasing a road bike or a single gear bike. I am looking at spending no more that $500.00. I know that is not too much money to spend on a bike (if I am wrong please let me know). I just want to know what bike to get and where the best place for getting on is (local bike shop, online, craigslist, etc.)