I used to play competitive A LOT when I was younger, my best was 3rd place for an all Ontario (Canada) competition and I won some county competitions. But it got to the point of being too time consuming and too boring, all you're doing is memorizing openings and certain strategies for middle play and end game situations rather than playing.

Having said that I really enjoy going through the old Master's games. If you're into Chess then I suggest getting 'The Most Instructive Games of Ches Ever Played' by Chernev (http://www.amazon.com/Most-Instructive-Games-Chess-Played/dp...). He goes through each game explaining the strategy and contexts of the games and moves, really enjoyable if you're into Chess.

chessgames.com is a cool site for going through their archive of games. My favorite is 'The Game of the Century' with Fischer who was my favorite: http://www.chessgames.com/perl/chessgame?gid=1008361