You need to get their userid somehow... using the code I gave my post fetches these if you are working in vBulletin. If you have integrated vBulletin with your ladder script, you are the only person who is going to know how to get the userid.
The link structure is like this:
Code:
<a href="member.php?u=VBULLETIN_USERID">My Profile</a>
You need to find out how to change VBULLETIN_USERID to their actual userid. We can't really help you any more then that.