Originally Posted by Ulquiorra X
He was in whiterun for me. I would recommend checking out all the Inn's in each major city. You will come across him eventually.
This ^ I hung around the Inn in Ivarstead and eventually just gave up and moved on. Ran into him shortly later on in Whiterun. The x360a guide mention that he is showing up in different places for different people. Just keep looking, it's a fun quest