There are many, many websites that exist which are devoted to blackjack. 
Here is just a small offering of some of the better sites that I have found:

Blackjack.Com
The Blackjack Page
Blackjack Bootcamp
Blackjack Without Tears
Blackjack in South Africa
A Guide To Blackjack Books
The Blackjack Review Network
The Blackjack Basic Strategy Engine
The Official Site of Lawerence Revere
Frequently Asked Questions about Blackjack
Learn Pro Blackjack's iPhone and Android apps