Mac Book Pro and Win xp network, can't see windows sharing in Mac

greeting all....having difficlty location the "windows sharing" option in the sharing componet of system preferences. Currently, my new laptop(mac) sees all of my winxp computers but not visa versa. Am a bit confused to why? I have looked for the Windows Sharing option in the preferences area but not there. Am I looking in the right place....thanks newbie to mac!

It'll be under the Sharing icon in the System Preferences pane. Cheers

You'll need to turn on sharing on the mac as mentioned, but you'll also need to make sure the firewall settings allow those computers to see your mac. ( or be off)