Question 1: Why can't I find the information you said was on the web site?
ANSWER: Your browser may have cached an older version of the page to which the information has been added. If you click the reload button of your browser you will obtain the most current version of the page in question.
Question 2: Are there any online resources for learning about search trees?
ANSWER: Here is a list of links to some nice applets:
1. http://www.seanet.com/users/arsen/avltree.html
2. http://www.cs.mcgill.ca/~cs251/ClosestPair/BalancedTreeApplet/BalancedTreeApplet.html
3. http://www.ececs.uc.edu/~franco/C321/html/RedBlack/redblack.html