I like Hetalia (bought the book ) xD But I like
Blue Exorcist (Satan's son wants to become exorcist) and
Gate (4 powerful animals are inside of 4 students. They have to go back to their dimension).
Pandora Hearts is a good one too (Oz becomes 15 and during a ceremony he comes to the Abyss [only criminals come there]. He can escape but is hunted for a deed he doesn't know).
Only the flower knows is yaoi^^
Death Note (Light finds a book. Every person he writes in dies).
07 Ghost (Teito was on an military academy but finds out the truth about his past and has to escape).
I often read doujinshis too, they're no real manga, but they're great^^