Remote users

Hi,

I run a network for a CPA office and all my PCs are Win XP Sp1. We have auditors that go to clients without Internet connections. I have purchased a wireless sonicwall VPN device and set up a VPN to VPN that works fine. I want to be able to use this same device for client locations with no internt connection. This will create a wirless lan. I want to have each laptop share files. I tried to do it with 2 laptops and the only way it would work was adding them to a workgroup, setting up a local generic account and mapping drives to each C share. Is there anyway to have the user laptops share while not connected to the domain but logged in theri"cache" domin account?

Any suggetions would appreciated..
Rob