Right, exactly what have you got?
2 PC's, I presume a wireless router? (when you mention USB adaptors, are these USB Wireless adaptors?)
The internet working fine on both of the PC's?
Simpliest way to do it, in my opinion is to go to control panel, system, computer name and then click on Change at the bottom.... chose workgroup, and then in the name box put whatever.... do this on both pc's, but they must be both on the same workgroup.
Then simply drag whatever you want to share to the shared docs folder... to access on either PC, simply go to start > run ... type in whatever the name of the other pc is (e.g \\steve) ... hit enter, and you'l see your shared folders.
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