This Avalon Hill Submarine reference CD has everything you need to make your game playable! -
Game Rules in PDF format
Game charts, log pads, counters, and variant counters.
A JPG map of the game board - so you can mount it to the wall on a steel sheet and use magnetic counters (see below for printing info)
Plus - A PDF with Avalon Hill General magazine articles in it (48 pages!)
This is a very nice to have addition for the game with scenarios, variant counters, and additional rules, commentary, and discussion.
Special thanks to Vince Redolf for reviewing this material.