USB Tethering:
Here is the thread I used mine set up. I'm also on Sprint, using the stock 6.5 ROM. Works great.
http://forum.ppcgeeks.com/showthread.php?t=115051
You will need to install a registry editor first. I use PHM Regedit (attached to this post).
WiFi Tethering (using your phone as a wireless hotspot):
I've attached the XDA-Tom_Codon CM Wifi Internet Sharing VGA.cab that I use. This also works perfectly and does not interfere with the USB tethering app, meaning you can have both installed to have a choice of how to tether. I can't remember which thread I got this from (if anyone knows the link, please post it!).