Hi,
I would suggest a Dopod 838 Pro, now known as the HTC Tytan II. I have the previous model and its a great phone.
Full 3G, hspda 3.5, bluetooth, wireless. Qwerty keyboard and heaps more. I use it as a GPS, Skype phone, video player, mp3 player, chat on it, full internet browser, the list goes on. I can even run a citrix client and logon to production windows boxes for support.
I have the previous model. The current model i beleive has a built in GPS radio, for mine i use an external bluetooth gps.
http://www.htc.com/www/product.aspx?id=640
Cheers Paul