Yahoo has plans to remove the "free" search tool. Here is a tool that you can use in the meantime.
http://freekeywords.wordtracker.com/

Three tips for getting past the personalized search -
http://searchengineland.com/070208-134406.php

A huge - and I do mean huge list of articles on linkbaiting.
http://www.cornwallseo.com/search/index.php/2007/02/09/the-enormous-linkbait-list/