Tabs Control

I am looking a tabs control is exactly the same as used on this forum. For example on the write a new post page, they're are tabs for compose, options, related and preview. I am looking to download a control te same as this. Anyone know where I could find it?You can download the code atCommunityServer.org.
I downloaded it but can seem to find the control, where is it located?
Please help!
Assistance would be great as this is very important.