file and printer sharing

Hello there, we have a modem /dsl at home and I configured my 3 computers to share files and printer after doing this I cant view the folders of the other computers file for sharing, where can I go to view the files shared by the other computer? if I go to RUN and type \\ IP address of the other computer pop up appear "network path was not found", we ping each other and its OK ,also I cant connect to the internet when we are all (LAN) connected as a network. please help and would be appreciated very much, Thanks guys and God bless ....