ATI equivalent of dualview (allowing 3360x1050 res)

I'm wanting to run World of Warcraft across 2 screens. To do this, my desktop resolution needs to be 3360x1050 as opposed to the current 2x 1680x1050. I know one can do this with the nvidia dualview (I think it's called) tools, but I'm looking for the ATI equivalent. I had a poke around in the catalyst control centre but didn't find it.

Can anyone tell me how I can set my desktop to count as one monitor @ 3360x1050?

It's in the CCC under displays Manager. You just right click the second monitor and choose extend desktop to this monitor. Extended desktop is what you're looking for right?

That is no different to how I have it now - I have 2 displays, each at 1680x1050. I need to have a desktop resolution of 3360x1050 so that I can run WoW at 3360x1050. I have tried forcing this res using the wtf files of the game, but it doesn't work.

I believe in the CCC, there is a setting for Span. That will stretch the display to look like one large monitor in Windows. Extended Desktop will still appear as 2 seperate monitors, but the Span feature merges them to one. I could be wrong, but I think that is what it is called.