Best way of sharing files over network with linux
Simply use the File Sharing option in the System Preferences.

It will give you the option to share using AFP or SMB, both of which are supported in Linux.

You didn't specify which Linux distribution you are using specifically, but most graphical distributions such as Ubuntu have SMB support out of the box (just go to Places->Network and find your share). AFP support can be obtained by installing afpfs-ng.