Two search engines you don't want to miss

Really.
With the thousands of search engines, directories, portals and meta-search engines to guide our way through the ever-expanding web, it's become ever more necessary to find a few good guides, use them often and learn them well. Allow me to suggest a couple to add to your inner circle of search engines: Bookfinder.com searches dozens of used book search engines and web sites. Instead of separately searching AbeBooks, Alibris, Amazon, Powell's etc. you can go to one site and search them all. It's fantastic!
Argali.com does similar magic for online phone directories by searching multiple engines at once: Yahoo, Anywho,Infospace, Google, Switchboard, Superpages and more. It's the best.
--RL