Writer Beware:  The most trusted source I know of for avoiding writing scams, from shady agents to outright rip-off publiushers. If you're looking to get published, these are the folks to check each name in the process against to make sure you're dealing with legitimate players.

Writer Beware (website)
http://www.sfwa.org/for-authors/writer-beware/
Writer Beware (Facebook)
http://www.facebook.com/WriterBeware?ref=ts

Absolute Write:  A terrific resource for info on the craft and business of writing. The Absolute Write Water Cooler is a great community for aspiring and published writers to keep up with things that are happening, and connect.

Absolute Write
http://absolutewrite.com/
Absolute Write Water Cooler
http://absolutewrite.com/forums/index.php

Preditors and Editors: Since 1997, Preditors and Editors has been a valuable guide to publishers and related services. If you're dealign wiht a publisher you've never heard of (particularly if you're going through a small press), Pred-Ed is a great place to look to make sure you're dealign with a legitimate company. 

Preditors & Editors
http://pred-ed.com/

Agent Query:  One of the most complete and easy to use databases of literary agents I've found. If you've written a book and you want to find an agent, I suggest looking them up.
AgentQuery.com
http://www.agentquery.com/
An article...no wait, a couple of articles, okay several articles from "Making Light" that writers should read.
http://nielsenhayden.com/makinglight/archives/005540.html
http://nielsenhayden.com/makinglight/archives/005555.html
http://nielsenhayden.com/makinglight/archives/004772.html
http://nielsenhayden.com/makinglight/archives/004772.html
Scam Alert page on SFF.net
http://webnews.sff.net/read?cmd=xover&group=sff.publishing.scams&from=-10

For every writer who asks "What do I do now?" at the end of finishing their book, I created this page to point you toward the people who can give you the best, most trustworthy answers in the industry.

I'll add to this page periodically if I find new resources that can hold a candle to these