This will show you how to play World of Warcraft without paying!!! There are servers that instantly give you level 80, free items, etc. There are also just regular servers if you want to play for real. Note: you may need to pay for the actual game, but not the monthly fee Blizzard charges. (But there might be free downloads of the game out there.)
Step 1: Install WoW
Make sure you have World of Warcraft installed, including all the expansions and patches.