Well, I've read the first book of The Missing by Margret Peterson Haddix. It's an amazing book. Here is what the description on the back says:
Thirteen-year-old Jonah has always known that he was adopted, and he's never thought it was any big deal. Then he and his new friend, Chip, who's also adopted, began receiving mysterious letters. The first one says "You are one of the missing." The second one says, "Beware! They're coming back to get you."
Jonah, Chip, and Jonah's sister, Katherine, are plunging into a mystery that involves the FBI, a vast smuggling operation, an airplane that appeared out of no-where, and people who seem to appear and disappear at will. The kids discover they are caught in a battle between two opposing forces that want very different things for Jonah and Chip's lives."
Okay, that is all I'm gonna type XD
I really think that you will like it, cause it's somewhere between science fiction, realistic fiction, and a mystery.
You may like the books "Percey Jackson and The Olympians" Sadly, I can't remember who's the author is, and my book is at school D: It's an awesome book that fantasy, basically. It is also a series, and it's first book is "The Lightning Thief" It's basically about a half-blood prince (reminds you of Harry Potter, does it not? XD) that has just learned that he is a half-blood and The Olympians. Percey, the half-blood prince sets out on a journey to save his mother and to try and return a lightning bold back to Zeus, after getting it back from Hades, but only to find that he really had the bolt all along. It's a fantasy and and an adventure, also an awesome book. You should check it out as well as The Missing ;D
P.S. Hi Sango! =D
~Mew