Baseball-Reference.com Stats
Up-to-date major league baseball statistics for each player, team, and league in baseball history. includes batting, pitching and fielding stats along with leaders, managers, links, books and award winners.
http://www.baseball-reference.com/
College Baseball
College Baseball
http://sportsillustrated.cnn.com/baseball/college
High School
High School
http://www.hsbaseballweb.com/
Little League
Little League
http://www.littleleague.org/
Team USA
The official usa baseball site
http://www.usabaseball.com/