This screencast shows you how to use FormsAuthentication on a Windows SharePoint Services 3.0 site (WSS 3.0).
It then continues with showing how to enable multiple authentication methods on one site (using Windows authentication and FormsAuthentication simultaneous).
Last but not least it shows how to create a page in SharePoint that let you administrate your users that uses FormsAuthentication (in this case how to create new users).
Oh, yeah. It starts where https://channel9.msdn.com/ShowPost.aspx?PostID=314283#314283 left off.