questions about Pocket PC?????

I need a pocket PC that will be compatible w/ Quickbooks. I am an electrical contractor, and need to be able to take my customer info into the field. I have also heard that I could have the ability to be in wireless/cellular contact with my office PC. Is this possible w/o spending a vulgar amount of money? Is credit card billing also a possiblity? What make and model would be best? What kind of software would I need to buy?

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