So where will they be ? And are there bigger ones then others?

Elseweyr, the moon, and Oblivion. They'll do it just to piss us off.

I heard there all in the clouds.

There's a thread for this on the first page.

http://www.gamesas.com/topic/1408125-guessing-where-the-plots-are/page__pid__21481754#entry21481754