Big Time Sites
Lycos
Yahoo - Also offers FREE Email accounts
Infoseek - Allows two step refinement
Excite
Netscape - Menu of several others (Excite, Lycos, etc.)
WebCrawler
HOTBOT - allows complex specifications
ICQ - they also have a very robust and popular chat software for FREE

Lesser Known
BotSpot

Personal Sites
Allan's Collection
Aim's Community School
Infinisource - extensive index of search engines by catagory