John, those are great links! Joel is very clear and his instructions are both well written and well illustrated. Reemas, if you haven't gotten file sharing and such enabled on your computers yet, those links are GREAT. However, if you already have file sharing set up on both computers, you can see if it's working by trying GO>Connect To Server. That should show you the PC that you're connected to, or at least the shared resources on it.
From the PC, (and I'm assuming you're using Windows XP-the process is different for different Windows versions) use Start|My Network Places and select Add A Network Place from the left hand window. From here you can use the wizard and choose the "Choose another network location" option. That should make the PC scan the network for available shared resources-like your Mac.