Teathering works like a champ... I've done it twice now on two seperate occations on two seperate computers... here are my directions.. hope it can help you out.
You need to DL the free version of PDANet on your EVO.
On your computer: First Dl this:
http://www.htc.com/us/support/evo-sprint/downloads/
Then DL the appropriate version of this:
http://junefabrics.com/android/
make sure your computer downloads the drivers for the EVO, did it automatically for me after I installed HTC Sync.
connect your phone via USB and select just charge.
you may need to go Settings--> Applications--> Development... and set "debugging" as appropriate (cant remember if its on or off)
open PDANet on your phone.