Have you checked out the T-Mobile Pocket PC Phone Edition (in the US, if you are outside of US it's the O2XDA)? It has all the Pocket PC features including MS office apps, Pocket IE, Windows Media player, etc. plus the phone and data capability. Read our review if you haven't done so: http://www.pdabuyersguide.com/tmobile.htm
In addition, you can check out what Sprint PCS has to offer. They have Treo 300 by Handspring, Samsung i330 and Toshiba 2032SP. Kyocera also has a new smartphone with touch screen coming out in US with larger carrier as opposed to the current Alltel service. Tungsten W will be out in the US which runs Palm OS.
The iPAQs can be turned into PDA/phones with accessories, though iPAQ 1910 can not use the sleeves which take CF card format or PC card format. It wouldn't be a good choice if you want phone features.