File sharing on a LAN

Hi First thing to say is I can never really get to grips with networking, however much I read about it. Nonetheless I have two machines both running SUSE 10 on a LAN. I have it set up so that it works to the extent that I can see the outside world from both. What I can't mange to set up is file sharing between the two and logging in from the second machine to my home directory on the main machine. What please are the easiest tools to attempt to use for this. The LAN is connected to the internet from an external router/adsl modem if that helps. Thanks Mike