Home network

I recently created a home network between two computers running XP Pro (freshly installed on both). The connections are through a router; the ISP (broadband) hits the router and then two network cables go from ports 1 and 2 to the respective computer NIC cards. Very basic and easy. However, at first, when I finished running the wizard on both machines, you could see each machine in "network places" on both machines. However, now you cannot. I've run the wizzard several times and made sure the network group name was the same, yet still the machines aren't showing up on the other's network places (no browsing is available). Can anyone suggest a solution, where I can get these showing on the other's network connections and are able to share files, etc?