Yes you can buy an External Bluetooth GPS Receiver. I recommend \/\/ \/\/ \/\/.buygpsnow.com/ Their service was excellent and their prices were on par with EBAY!!! (That's good) I bought a Holux M1200 Because it is very small (I put it on my keychain!), reliable, and great battery life/charge times. Don't worry too much on how many channels there are... depending on how many Channels a GPS receiver has dictates how many satellites it can track at one given time... the more the better right? Wrong. I have seen a 60 channel GPS receiver! That is stupid. There are currently 27 GPS satellites in Geo-Synchronous orbit. Only 24 are in operation... 3 are reserves in case a satellite stops working.
http://en.wikipedia.org/wiki/Global_Positioning_System
On another point.. these satellites need to be more or less line-of-sight to your receiver.. so since you cant even pick up the sats on the other side of the world, they don't matter. OK, the point is you can only utilize 12-13 or so at any given time. Don't waste money on overkill.
Now.. time is an issue for you... The Mogul's Qualcomm processor has GPS built into the phone, it just hasn't been utilized by HTC/Sprint for some reason. They are going to release a ROM update to take advantage of the built in GPS receiver "Early 1Q 2008" according to HTC's web site.
http://www.america.htc.com/support/m...dDeviceId=8997
So you have to decide on if you want to Wait for free GPS... and a solution that will render carrying and external one pointless.. or if you want it NOW!
Later,
phaZed