Create AD User in SharePoint

http://www.a2zdotnet.com/View.aspx?Id=111

PowerShell
http://www.toddklindt.com/PoshMakeUsers

http://www.sharepointlonghorn.com/Lists/Posts/Post.aspx?ID=81

http://blogs.sentri.com/2013/01/how-to-create-active-directory-users-using-powershell.html

You can also build your own web part from visual studio or purchase one from a third party such as bamboo http://store.bamboosolutions.com/sharepoint-user-account-setup-web-part.aspx  Note the free trial