Illustrious 18
Don Schlesinger's Illustrious 18 is a good place to start if you want to incorporate count based strategy variations. If you Google it, you can probably find it on the Web. It is also in Schlesinger's book, Blackjack Attack, which I would highly recommend. For more strategy variations, look at Wong's Professional Blackjack, which is also a must read for Hi-Lo players. If you are relatively new to the game, you may want to give my book a try as well. It is Bootlegger's 200 Proof Blackjack.
Strategy variations are an important part of the counting game, and add to your bottom line. While this is true with any number of decks, it is especially true in single deck games. The Illustrious 18 captures about 80% of the gain that can be had from strategy variations, and I believe every counter should know at least those key plays.