are both computers in the same workgroup/domain? if so, share a folder (right click, sharing) and then check My Network Places on the other PC and see if the folder appears.
the Shared docs folder is just for different users on the same PC (iirc? don't use it =p, i just share folders accross networks)
i had the same problem, Click start> search > then computers or people > computers on the network > then type " ip adress other the other PC here" then all the shared folders should appere and all the printers ect...