LG USB Driver

so have you used this? does it work?

Didn't work....

LGUSBModemDriver_Eng_WHQL_Ver_4.9.4_All.exe does not work.

But, user Joker416 on HowardForums was nice enough to put the CD up.  The drivers and install on the CD do work.
http://www.howardforums.com/showthread.php?t=1540705

If anyone with a data cable can get the PC Suite 2 software to do anything more than report it's connected (viewing Contents, Contacts, etc) please let me know.  Mine just says the connection to the phone timed out.  I am using data cable LG-DLC100 and the same cable works fine for Mass Storage mode (which doesn't need special drivers) and I can talk to the modem from the PC, so I'm not sure why PC Suite can't view stuff.  Maybe AT&T has locked the functionality out?

As predatordfl says, BitPim doesn't recognize our phone yet (and I tried all the existing LG options)... so hoping it does soon!

Strange, me too...
Here's the link that was in the thread (hope it's okay)
http://www.megaupload.com/?d=YKIEVYB0

Did you pair your PC to the phone and set your PC's ID on the phone to Auto-connect?

Otherwise your Xenon will ask for permission, and if you don't OK it, then it'll timeout and disconnect.

I just talked to the modem over the Bluetooth Serial Port and it worked (AT responds with OK) but after I disconnected the terminal session it disconnected the Bluetooth connection too.

Yeah, both Music Sync and Mass Storage modes work.  I just can't do anything while in Data Service mode - except for tethered Internet access.

Install the drivers from the Xenon's CD.  It installs as LG MC USB U330 Driver, though I previously had found other drivers with the same name that did not install for the GR500, so use the one from the CD.  (So the CD is useful - for the drivers at least)

When you connect your phone to your PC, three virtual serial ports (COMn) ports will be installed.
Make note of the "LG Mobile USB WMC Data Modem" one.

Create a new Dial-up connection.
Enter WAP login and password.
Enter phone number *99***1#

Then connect as you would a normal dial-up modem.
Once you verify the connection is working, you can go to the Properties the next time and un-check Prompt for name and password and Prompt for phone number on the Options tab.  This will skip the prompt (assuming you let Windows save the password).

Note that your mobile provider may have rules that restrict, prohibit or even bill you for tethered access.  Some may even had disabled tethered access in the phone itself.  So YMMV, but I can say it works for my carrier.