It doesn't matter if wired or wireless, same changes in Windows 7.
If you are just trying to share folders or volumes between computers on a small LAN you just need to right click on the folder or drive and change settings in TWO tabs -- sharing and security.
If you want anybody on the network to have access after you set the folder/drive to be shared under the sharing tab, open the security tab, click edit, click add, then add a user group called Everyone and set their permissions. You can also just add individual users in the security list.