Someone please help me, new battery question & taking too long to charge
 

I know there are threads about this, but I think I am confusing myself. The Seidio cases, I am going to get one I think, however, I also want an extended battery, where do you get the new battery covers? And also, will sprint void the warranty on the Pro or does HTC make an oem extended battery? I also want some sort of charging station, even if I get an extra standard battery, so I can just swap them out. Where is a good place to get an OEM standard battery and station for a good price?

Also wanted to know if USB charging is bad? My phone did not come with the AC part when I got it a few days ago and I have been doing USB charging, and let me just say, it takes like 5 or 6 HOURS to charge this way and it sucks...

Thanks