Is there any 1man game similar to World of Warcraft that is not an online game

Pretty much any game that has to do with medivel times. There is a family of games based on the Forgotten Realms of D&D, which can be played offline. You can go to http://en.wikipedia.org/wiki/Forgotten_Realms if you want to find out about them. They definitely have the feel of WOW, without the online problem. If, on the other hand, you decide you want an online option, it exists.