If you got the Samba stuff installed, chances are that you have SWAT (the Samba Web Administration Tool). To find out, point your browser to
http://localhost:901/ and see if you get a login. Login as root, and you should have a nice web GUI to administer your shared folders and whatnot.
However, getting at (and mounting) shared folders from an XP box is somewhat trickier. I've been struggling with it for a while and haven't reached satisfactory results. If your two machines are networked through a hub or router, then the first step is solved; you should probably try a number of simpler tests to be sure the two computers can see each other, though. There's a good introductory
Networking Overview that you may want to look into before you work on sharing files and whatnot.
The best Samba resource I know of is
Using Samba, available for free from O'Reilly's website.