I knew that there had to be a listing for these things out there somewhere.
First, there’s the Web Fiction Guide, where you can bookmark and review a large number of online stories, as well as search for ones you might like by very detailed tags (REALLY detailed tags). It’s a great site.
Web Fiction Guide (online novels, reviews)
Then there is Novels Online, a directory that can be sorted by rating, genre, status (finished, actively writing, etc.).
From browsing through the titles, I learn that online novels overwhelmingly have three of the following supernatural creatures: vampires, werewolves, and zombies. I’m pretty sure that Ash and Zabe doesn’t have any of those. Don’t ostracize me, online novel community! 
Actually, we have a lot more “post-apocalyptic” stories than ones about either “werewolves” or “zombies”.
There are more listings than that. I list some of them here:
http://sites.google.com/a/vonsbooks.com/www/home/links
And I don’t have any of those types of characters either. I wonder why they are popular.