Guitar center has some cheap Fender guits out there...
You can get a mexican built telecaster for around $249..not sure what the Stratocasters run for.
I would buy a new, less expensive guitar if a beginner. Looking for used guitars can be a pain. Put it this way - most musicians dont make too much money, so if selling equiptment -they can smell a new guy coming. In the end you might think you're getting a great deal, but actually end up with an overpaid piece of junk.
You can check online also. I wouldn't be too scared of ordering a guitar online, if you are a beginner. Although it is nice to be able to play what you buy, you can test a model out somewhere at a store and find one online. After you recieve it, you can take it somewhere to have it set-up or do it yourself. But chances are, if you're just beginning - you wont need to have it set up.
For a beginner I would reccomend a guitar with out a tremolo unit, unless you are looking for a Strat type guitar. You could develop tuning problems with tremolo if not set up properly.
I would go with a telecaster, or possibly a danelectro...
Stay away from the cheap Gibsons or epiphones - they'll never stay in tune if you don't know what you're doing. Most of those need the nuts replaced and recut. Even on their high dollar Les Pauls - need some work on them before they're playable from the factory.
http://www.music123.commusicians friend -
Guitar center.