Samaba is a two part program, samba client is used to go from linux to another system with windoze shares, ie your XP system. You do not need samba server to do that.
You did not state what desktop, or distro you are running. If it is KDE, then open Konqueror, and in the search bar, try this, type smb:/bar.server.no/ and see if you can get a graphical response. If you can see the server, then you should get a image of the sever. Click it, and see if you can see the shares. If it is password protected, you will get a request for user and password.
I'm not as familiar with the clients in Gnome, I know there is one, same approach there. You could also install a program called LinNeighorhood. It works in a similar fashion to Network Neighborhood in windoze.
To get from XP to linux, you need samba server running and configured. You also need to add samba users to your samba configuration. If you need help with that, you will need to post your /etc/samba/smb.conf file. There are way to many options to help without more specific information on the configuration. There are tools to assist configuring samba. Swat is one of the best.
There are also tutorials on this. For example, look here to get started --> http://www.linuxquestions.org/linux/...k_File_Sharing
Hope this helps.