File sharing problem/question (long)

Sorry, but search is currently disabled so was unable to
see if this has already been answered: Have 3 desktops on
MS network using "g" equipment. Machine "A" is where
cable modem and wireless router are attached. "B" machine
is where one printer is located, and "C" machine has
another printer. Here's the problem: I want to be able to
access multiple "my documents" folders, or preferably the
entire hard drive on each machine from each machine. All
are running WXP. "A" can read all of "C", including full
hard drives, and can print to "B" and "C." "C" can
read "A" and can print to "B" and itself. "A" can read 2
users from "B" but not the other 2 (4 users in
total). "B" cannot read any users from "A."

I have deleted and re-shared the hard drives, the my docs
folders, and the individual users docs folders several
times, using the sharing feature, and also from the
network connections tab wizzrd, and can't get "A: to read
more than 2 users from "B." All users are administrators;
I've tried disabling the windows firewall, and tried
unchecking the client for MS networking box; all machines
are in the same workgroup; all machines "see" the others
on the network, but can't access the documents. I have
not (intentionally at least) adjusted any permissions
anywhere.

Any and all suggestions and ideas are welcome. Thanks.