The following links may be helpful. Some of them I've used myself .
Dictionary.com
Merriam-Webster Online
YourDictionary.com
ForeignWord.com
OneLook Dictionary Search
OneLook Reverse Dictionary
Freelance Writing Organization ( A fantastic free resource for writers-they have an extensive database)
Netfirms.com (for $9.95 a year, you can register your domain name and
get free web-hosting. They'll even send you a website-starter CD upon
request! Excellent for writers trying to promote themselves on a small
budget)
FirstWriter.com ( really invaluable resource for writers. For a very
nominal fee ($2.99/month, $7.99/quarterly, $28.49 annually), you get
access to tons of relevant information like agent listings, magazines
you can submit to, and more)
How To Promote A Book for Free
(good information for free)
Writing.com (another really good resource site for writers. Membership is free but to take advantage of all they have to offer, paid memberships are offered).