Pamela, I had the same issue yesterday when I finally got to author page, problem was I was trying to place the Edit link outside of the 'listing' .
It seems to be a major feature flop for a classified site of any sort – it appears you can't call for a list of ads with edit/delete links next to each, you can only have a list, and once you click on a listing, you can place edit/delete links inside.
I have done it the way you did, and got a blank page. If you place the edit/delete in listing view, everything works fine.
