Frozen Fire by Tim Bowler. It is supernatural and it is really good. It has a mysterious sense to it as well.
The girl in the Steel Corset by Kady Cross. I have just finished this book recently and thought it was really good. I would think it to be supernatural. It is based in the late 1800's and also has "robots" in it.
I have never read Fallen so I am no help there but you should try both this books I recommended above.

Based on your book suggestions, i really think you might like Firelight by Sophie Jordan. It's about a species of human called "draki". draki are a small group of humans who can shift between dragon and human forms. Jacinda, the main character, is rare among her kind. she is the only fire breather ever to live in 400 years, making her more popular then she ever wanted to be. The only thing that revives is Will, whose family hunts her kind. Jacinda falls in love with him, even though she knows she's risking her life as well as the draki's most guarded secret. There is a squeal titled Vanish. coming out on 9/11 (i know, ironic timing) is the final book which will be called Hidden. you can find these books in the Teenage Paranormal Romance section at Barns and Noble, and probably other book stores as well.

Well the only two down sides to my suggestion is the books (unless you get them used) are1 about $10-$20 each. And that they only take like (well for me at least) 30 minuets to read. Although don't think it's a childs book. It is called "High School of the Dead". I have never read the searies myself, but I have herd good things about them. The only thing is I would hide it if you don't want.... well ... umm explicet meterial let's say to get into some people hands. Although they sound interesting and right up your ally. I am sure there are a bunch of other manga selections