Buy one.
I had the same problem and they gave me a new Rumor Touch with a it`s own problems.
Yup.If you refuse to deal with Sprint, you can get a brand new one on eBay for as little as $75.
Yep thats what i have done in the past (with my tmobile phones). I dont like signing a two year contract and being stuck. on ebay you can find pretty good phones for cheap
150 for a 520 is not cheap