Digital Librarian
A librarian's personal choice of best sites, by subject.

Internet Public Library
One of the better electronic reference centers.

Libdex
Libdex is a worldwide directory of library homepages, web-based OPACs, Friends of the Library pages, and library e-commerce affiliate links. The directory does not include links to terminal-based OPACs.

Project Wombat
Project Wombat is a discussion list for difficult reference questions, continuing in the tradition of the now-defunct Stumpers list. Anyone may join, or submit a question.

Rutgers' Electronic Reference Sources
Take your pick of the top ready reference collections.