There have been quite a few threads exploring this here so I thought I should recommend a set of fairly new fantasy books that explore it quite a bit, called
The Blackwood Saga, by Layton Green. The books mostly take place on an alternate Earth where wizards are in control of most of the world. The main characters have been transported from modern day Earth and one of them is an RPG player who has a day job as a swordsman in a Medieval Times-like restaurant. Very well done novels in my opinion...