The first thing you should do is take your new phone and get the latest Sprint ROM upgrade available here.
http://www.america.htc.com/support/m...downloads.html
Then you should bookmark that site and in a few days?! download the newer update which will enable the built in GPS and REV-A.
Search for HTC Home today plug in to get a better Today screen, and HTC Home customizer will make it easier to change the look.
From there, you will need to read, search, read, search, and in no time at all you will be flashing custom ROM's and have all that cool stuff yourself.
Search for things like.... 'post your ppc6800 today screen here', or 'HTC Cube'
but search and read we don't enjoy holding hands
Good luck and have fun!!