OK, so I have an Alltel Touch (Vogue). I tried to read all of the various GPS posts on all the different web sites, did many of the steps to get GPS on my phone. It worked for a little while, then stopped. I went to the HTC website, went to support, picked my phone, downloaded the Latest ROM. Bingo! No hack, modification or tricks, I have gps. I installed google maps from m.google.com and clicked "use GPS" from the menu and Viola it works. the ROM and instructions for the Alltel Touch is here
http://www.htc.com/us/SupportDownloa...at=2&dl_id=115. Here are the features of the new ROM per HTC:
The software upgrade posted below provides several key enhancements for your HTC Touch smartphone:

Upgrades the operating system from Windows Mobile® 6.0 Professional to Windows Mobile® 6.1 Professional.

Adds the ability to use the internal GPS of the handset for advanced location services such as Alltel Navigation, an application that provides audible turn-by-turn directions and business listings.

Adds a FREE Opera browser for improved web browsing.

Includes updates for network speed, allowing the phone to use EVDO Rev A networks.

Adds all enhancements included in previous software maintenance releases.
I would guess you could also go here
HTC.com and pick your phone/carrier and see if there is an updated ROM for whatever HTC phone you have.