Hey guys,
If you are struggling with ochem, of course Kaplan and Destroyer would be top of the list, but I also found this website which is pretty dandy when it comes to understanding some key concepts. Hope it helps!

http://www.asu.edu/courses/chm331/problems.html

Doesn't look half-bad, save that the first thing I clicked on was "mol. orbitals," and that "targeted" atoms by painting them red. I'm colorblind, so I couldn't spot them for the life of me. If they were bolder, maybe.

Other sections were alright. I wouldn't really call it a learning tool, though; it was mostly just drill problems with short explanations. About the same as you'd expect from the solutions manual to a text. If you're running out of end-of-chapter problems, I guess it's helpful.

No lie..I used these tests before every one of my organic II exams. They help a lot..just to show you where you stand at random questions. :)