If by a hand-held computer you mean a laptop, then you could jsut go to best buy. To tell you the truth, they sell notebooks there for the price they are on internet, but they have some feature upgraded. F.E. I bought this presario at Best Buy, and it cost $1799, but at the website, it had a rather slow processor, low ram, and a tiny HD for the same price + shipping. Go figure.
These don't require a cell phone, jsut a normal phone line, and an ISP like AOHell
If by hand-held PC you mean a tablet PC - tha'ts the news thing, then the only place you could buy them would probably be either in a companie's MAJOR warehouse, or online. These can be quite expensive. These however, DO require a cell phone - they are made to be completely mobile. Also, geting support for this thing is not easy - you cna't just go to staples and fix a thing or two - too new a technology.
make your choices.