Hello Ruben and welcome to the community.
These links can tell you volumes about the game.
Enjoy.
Community Manual :
http://www.communitymanuals.com/shii...itle=Main_Page
The FAQ:
http://www.subsim.com/phpBB/viewtopic.php?t=28146
Convoy interception :
http://www.subsim.com/phpBB/viewtopic.php?t=29992
Wazoo's Charting and Targeting manual :
http://www.paulwasserman.net/SHIII/