Here's a list of the top sites for the crossword puzzle solver. If you're struggling with a tough clue or are stumped by a difficult puzzle, these sites can be very helpful.
Hundreds of dictionaries are only a mouse click away. This resource allows you to search for definitions, translations, words beginning or ending with a certain word or letter pattern, wildcard searches, and even words related to a concept! Truly a one-stop, indispensable reference library at your fingertips. Over 12 million words in over one thousand dictionaries indexed as of July/2008.
This site bills itself as the Crossword Constructors Community Center so it's not technically a site for solvers. However, it's a great place for solvers to hang out and by learning a little about how puzzles are constructed they can improve their solving skills. There is also a puzzle clue database (access requires a small donation) where you can do wild card searches. Helpful when you have a partial fill in a crossword puzzle. I highly recommend visiting this site and joining the Cruciverb mailing list. Where else can you converse with the likes of Manny Nosowsky, Bob Klahn, Merl Reagle and other heavyweights of the crossword construction world.
Unlike pure pattern dictionary searches, One Across actually analyzes clues as well. Just enter the crossword puzzle clue and either the length of the answer or an answer pattern (use question marks for unknown letters).
The Crossworders' Dictionary & Gazetteer is the work of Will Weiss whose mother, Yetta Weiss, spent 65 years compiling the database. The entire database is available on a single CD. It not only makes possible the publication of this resource at minimal cost but it also allows users to access the information quickly and effortlessly.