Well as for how MySpace actually works when you edit it, I have no idea how to help you there. BUT, if it allows users to input HTML somewhere, you can try doing something like this:
HTML Code:
My Favorite Website is <a href="http://www.MortysTwistedWorld.com" target="_blank">Morty's Twisted World.</a>
It has a kickass forum, tons of humor content and a wicked arcade for its members. Check it out!
If this doesn't help out, hopefully my sister, username here on MTW is Morty'sSmellySis, will see this question and be able to help out since she has a MySpace account.