Hey... I don't know about MMORPGs but you can find Travians affiliate at Adjal. Travians pays $.40 per lead, which is online browser game. Hope, you will try... Best of luck...
Well With All My Respect to adjal Adsmarket Got the Most Games, More Than any Other Affiliate i have seen. They Have Travian - Bigpoint - ryamous - Gods war & More
Adsmarket do got quite many great games affiliate you can also try CJ.com for outspark affiliate program promoting games like project powder ...etc you can take a look at my game site for some handy references: free-online-games.withtank.com
If you have a look on Azoogle there is a Flyff affiliate. Flyff is an MMORPG, and I've actually heard of it myself, was a very popular game on a forum I used to use, but that was ages ago now. Maybe it'll still work. On Azoogle they paid $1.10 per download of the game, and they must download it directly from their site.
There are many!! We have some: Brain Age Calculator Send a Beer to Your Friend! Ultimate Genie's Lamp CA Jellysquirt Silly Games! Jellysquirt Puzzle Games! etc.