Now in its 10th year (15th if you count the books that pre-date the Internet), AllMusic covers every single solitary genre of music, has information on the most popular bands and the most obscure. I've used it religiously since 1997.
If you need to find the date an album came out, who sang versions of your favorite song or simply want to know when someone was born or their real name, you have to hit AllMusic.
The only drawback is AllMusic doesnt have news or links to other popular artist sites -- and sometimes it's slow to load, but that may be due to so many people searching at the same time.
Ok, you might have to pull out some hair.