I don't think anybody has mentioned Scott Westerfeld yet.
The risen empire is a brilliant space opera, told from the point of view of several characters, involving different human civilisations, one of which is lead by an emperor who has understood how to avoid death more than one thousand years ago, and therefore has been ruling for all this time...
It was written in 2003 so it just fits your timing requirements of 5-6 years.
I haven't read
Evolution's Darling, but it looks great.
Scott Westerfeld also writes a lot of books for teens, sci-fi or fantasy.
The
Uglies series is about a dystopian world in which everybody undergoes surgical surgery at 16, in order to become
pretty and spend their life partying with their pretty friends. When she's about to turn 16, Tally is forced to wonder if there may be more to life than partying...
I recommand this one most highly, for teens or adults.
Peeps takes an original view of vampires as people infested with a parasite. A quick read, but very good and gripping.
The
Midnighters series also looks interesting, though I've heard it's a bit inferior to
Uglies.
And a last book,
Leviathan is sold as a pre-order at fictionwise:
http://www.fictionwise.com/ebooks/b9...rfeld/??r=9a28
It's steam punk and looks really good, I'm still deciding if I'll buy it right now or not.
Of the books described above, the
Uglies,
Peeps and
Midnighters series are available as ebooks, as well as the newest one,
Leviathan.