How do you access files FROM a home network TO a CLIENT computer using "internet sharing" from a mac ?

Hi.

I just created a small network: 2 pcs and 1 mac.

2 pcs are using windows XP

1 Mac is using OS X

I would like to know how to access files from my pc1 to pc2 from my network.

Pc2 obviouslys is a client behind the intenet sharing my mac is providing.

I tried looking for the info online but most of the search brigns out "internet sharing" or "file sharing."

Any help would be great.