When I first started down this writing journey, I explored nearly none of the vast writing resources available. I was simply trying to prove to myself that I could write 80,000 words that all related to each other and formed some sort of plot. It wasn't until I finished my book, took a step back, and realized that I need some HELP, big time.
I had no idea how to begin revising, no clue how to find an agent and certainly in-the-dark about the publishing process. Thank goodness for the interwebz.
One of the first few websites I stumbled upon, back in 2005, was Absolute Write. And, four years later, I still read the message boards daily. It's an amazing resource for all writers--unpublished, pre-published or published. There's everything from query critiques to a place to rant and scream about agent form rejections.
Probably around the same time, I discovered Miss Snark. She stopped writing on the blog awhile back, but has kept it active. A wonderful, hilarious and full of invaluable advice, this blog taught me what a query letter should be, reminded me that those opening pages better be more than just backstory and challenged me with a question from an agent's perspective, "Why should I care what happens to your characters?" Or, "So what?"
In addition to those websites, I also love to visit other author's blogs, if even just to nod my head at all of the freakouts that mirror my own, or laugh when they want to kill off all their characters in revision. (Side note--I am just about at that point in revisions to my YA book. I really just want to delete everything after page 15 and have aliens or zombies show up and eat everyone. The End.)
My final, and probably best, resource is published books. The kind other people have written. I'm a person who learns best by example, so when I read a book and say, "Wow! Didn't see that coming!" or the like, I try to distill the "why" and the "how." Another reason why I love this resource? I can go into Borders, walk out with my poor pocketbook much, much lighter and call it "research."