Do a search for "frozen yeast bank". It walks you though the process of preparing your yeast for the freezer. I've started doing that will all the liquid yeast I buy and it works great.
Black Warrior Brewery
Primary's: Hob Goblin II, JOAM, Bleached Blonde Ale, Blonde Helles
Kegged: Imperial Honey Porter, JZ American Brown Ale, Scottish 80/-, Lake Walk Pale Ale, EdWort's Apfelwein, Parti-gyle Porter, Blueberry Blonde
Coming Up: Westvleteren 12 clone, Oktoberfast, SWMBO Slayer
Projects: Fermentation Chamber