Mac OS X has built-in capablities through Samba to play nicely with Windows networks. An early step to working seamlessly with a Windows workgroup is joining that network.

Open the Directory Access utility (under Applications -> Utilities).

If the window is locked (padlock closed on the lower left), click on the padlock to unlock it.

Select SMB and click Configure...

Type in the name of the desired Windows workgroup in the Workgroup field, enter a WINS server (if appropriate) and click OK, then Apply.