It's available HERE.

Also see THIS thread for more info.

http://forum.xda-developers.com/showthread.php?t=296912

Did you know you can enable the GPS functionality in the new-generation Pocket PC phone, the HTC Trinity (HTC P3600) with a simple, easy, free ROM upgrade? Did you know the latest ROM upgrade offers a significantly lowered boot-in time and slightly decreased (albeit still very bad) A2DP CPU usage, more wireless icons (E for Edge) and, last but not least, SDHC compatibility? If you didn’t but would certainly enjoy the advantages of the built-in GPS unit and the other goodies of the new ROM, make sure you do the following:

1. download the SSPL-TRIN.zip utility linked in from the first post of this thread (note that you’ll need to register yourself in the XDA-Dev forums to be able to access the file)
2. download the new ROM upgrade from here (Pacific users may also want to give a try to this Chinese source to see if it’s faster)
3. decompress both files. From the first, transfer SSPL-TRIN.exe to your PDA and execute it there, after disconnecting your Trinity from your desktop. You’ll see the standard rainbow-color bootup screen.
4. now, start the large RUU_Trinity_DOPODASIA_WWE_1.23.707.6_6275_1.35.00.11_108_Ship.exe file on the desktop, press the OK / Update / Yes buttons until it gets to flashing the new ROM.

It worked for everyone so far. Note that if there is “Serial” at the bottom third of the rainbow bootloader screen of the Trinity, the desktop PC won’t likely to recognize it. Then, just reset the PDA and, after booting in, just restart SSPL-TRIN.exe. You’ll need to see “USB” for the PDA to be recognized.

It was just some minutes ago that I've announced the availability of the brand new, GPS-enabled Dopod ROM for the HTC Trinity and I already have some great news for you all Trinity AND TyTN (Hermes) users:

XDA-Developers user Des has just released a tool that makes it possible to install any kind of ROM on your HTC Trinity AND TyTN phones (that is, a SuperCID checking bypasser).

UPDATE (02/14/2007): in the meantime, a lot has happened. Start right with THIS TUTORIAL / ARTICLE, it contains all the information you'll need. I, however, keep the original article too for historic reasons, which is as follows:

The HTC Trinity community, suffering from the limitations of the pre-release test ROM (the only ROM version to offer GPS functionality), has been waiting for the final version of it. Now, it’s here.

The great folks at XDA-Dev have just published the way to unlock the hidden / buried GPS functionality in the HTC Trinity. Please see THIS THREAD. A related thread at HowardForums is HERE.

UPDATE (01/26/2007): PPCT frontpage