Check out the Official Charlton Atheltic website
Also check out the international Addicks link as well http://www.cafc.co.uk/internationalmembership.ink
I've supported them for almost 10 years and can proudly say I'm Charlton till I die. I've been a fan since the first match I went to. You can either sign up for Valley vision or order one of the season review DVDs from the club shop to see past games. The club is now a well established Premiership side and have just been granted permission to expand their ground 'The Valley' to a capacity of 40,000!
Have a look and if you do sign up I can guarantee it'll be the best decision you'll ever make!