Holux M-1000 32 Channel Wireless Bluetooth GPS Receiver
I use this with my AT&T pantech duo phone and google maps and also live search and this thing will pick up a street even inside the house.  It was a bit difficult to set up because the instructions were very brief but if you go to the website [...] they have the full guide and after following that I was on my way.  Should work great with any smart phone using windows mobile.  Then you don't have to pay for those expensive GPS services through your provider!