You should first decide what it is you want the tablet for. For example, Netflix doesn't work on all tablets. Also do you want USB? Again not all tablets have USB directly on the device, you might need to purchase a docking station to get it.
With that said I have the Iconia a500 32 gb. $429 at Costco? The working USB and decent GPS, along with the ability to use external hard drive/thumb drives was the deciding factor.
I think that once you decide what is important you will be able to find a device that will provide those features at a reasonable price.
What ever you get enjoy.