Just a short plug for a great HP site. Whenever I get a bit loopy and lost, I head back to this website.
The webmistress is a genius--has a HUGE selection of commentary on Harry Potter. She also archives some fanfic stories, mostly Snape-centric, but some others. (One of the first SS/HG fic online is archived there... written by a 13-year-old in 2000, no less... wow.) You will find her site well-organised and well-written. There is commentary on everything there--from Aberforth and the Goat to Snape's Loyalties. She updated some of her commentaries on 31 October to be HBP-compliant.
SO, do not visit unless you want to be spoiled.
www.redhen-publications.com (don't forget the hyphen)
My favorite article:
On the Good 'Ship Granger-Snape.
EDIT: Sorry, got the right address. *facepalm*