As some of you might know, I have a ton of websites that I go to to get extremely important information on the bands I research and without any further ado, I'm going to list them and give you a small idea of what those sites do...
Absolute Punk: Great resource of news regarding the most popular pop-punk, post-hardcore, and metal bands. Champions smaller artists.
All Access: Radio industry website. Posts information about jobs, particular formats of radio and the songs and artists going for adds from week to week. (registration required)
Billboard: Probably the most popular of these resources...this site goes into detail regarding chart-topping hits.
Crazed Hits: A&R resource that showcases unsigned artists. Featured Katy Perry, Colbie Caillat, and One Republic before they got signed.
FMQB (Friday Morning Quarterback): Summarizes music news and posts songs going for adds in particular formats.
Hits Daily Double: Posts music news in detail and posts estimates of weekly album sales a day before Billboard posts final numbers (registration required).
I Heart Music: Clear Channel gets so much crap for not playing new music, but this initiative that they have of trying to get independent artists play is great. Even if they don't, you'll probably discover an artist that you like. They also play occasional album streams and their unplugged series called "Stripped".
Kings of A&R: Similar to Crazed Hits in that they're both A&R resources, but this site is a bit more into detail.
Myspace: Just remember that if you don't have one, you don't exist.
Plugged In: Great music video website that shows videos in HD.
Purevolume: Great music website that seems to post more exclusives than Myspace. It's almost like a Myspace for members of Absolute Punk.
Tunelab Music: My personal favorite resource because it has music news for the kind of bands that I listen to and that I'll post here.
Videostatic: Great music video website that posts music videos and information about videos that have been or will be shot.
Youtube: Great website to find live and rare performances and music videos you haven't seen in years. Not so great for the quality...but the fact that it's there is more than enough.
I may find more over time, but these sites have NEVER let me down. Unless they themselves are down.