I typed words “cooperative online multiplayer game” in Google and wanted to see what kind of list of games I could get. Well, not a huge one. Take a look at here:
In the top of the list, I could see list of cooperative games for Xbox 360 (Wikipedia).
Then, quite near the top was some free coop game (I have no idea what this game is)
And then there was some links to discussion about “where to find cooperative online multiplayer games” – threads such as this.
Interestingly, from (physical) board games, there’s a big list of them available (at board game geek).
Where are the coopeartive online multiplayer games located? Who is publishing them?