My favourite books/series would include:
Harry Potter
Twilight
Tales of the Otori
Noughts and Crosses Series by Malorie Blackman
Cherub
The Boy Soldier Series by Andy McNab
Alex Rider
The Kite Runner/A Thousand Splendid Suns
All Eva Ibbotson's books

I'm looking for new books that are similar to those above, either from teenage/older readers or otherwise.

Thank you!!

I've posted this in the other section too!
Angie Sage has written a wonderful series with the central character of Septimus Heap. 'Magyk', 'Flyte', 'Physik' and 'Queste'. Well worth reading.

I also cannot recommend Phillip Pullman's 'Dark Materials Trilogy', 'Northern Lights', 'The Subtle Knife' and 'The Amber Spyglass' enough!

I am also a big fan of Terry Pratchett - anything he writes. Finally Neil Gaiman has written some great and quirky books.

The Tunnels series by Roderick Gordon and Brian Williams is superb, 3 books so far - Tunnels, Deeper and Freefall. For confident readers 10+ (A Richard & Judy Children's book finalist).

Also excellent is - Jonathan Stroud's Bartimaeus trilogy, P.B.Kerr's Children of the Lamp series and Stuart Hill's Icemark Trilogy.

Try 'A Wrinke in Time'

Try evermore by alyson noel or the vampire diaries series by lj smith both are about vampires.

SCABS by G P Sirod

The Dragon Whisperer by Lucinda Hare which is about to be published is just what you are looking for. Excitement, great characters and a very real world. This is the first in a trilogy. A friend of a friend gave my kids a preview copy and they are addicted.

The Dark is Rising series by Susan Cooper are fantastic - five in all as follows:
Over Sea, Under Stone
The Dark is Rising
Greenwitch
The Grey King
Silver on the Tree

Enjoy!

Okay, here goes -
Stravaganza series by Mary Hoffman
A Great and Terrible Beauty ( trilogy) by Libba Bray
City of the Beasts trilogy by Isabel Allende
Inkheart trilogy by Cornelia Funke
Maximum Ride series by James Patterson
Mortal Engines series by Philip Reeve
Bartimaeus trilogy by Jonathan Stroud
Bloodchild by Tim Bowler
A Bridge to the Stars and sequels by Henning Mankell

Hope this is helpful!

Fantasy wise, I would suggest The 'Study' series by Maria V. Snyder (Poison study, Magic Study, Fire study). They weren't exactly my cup of tea, but who knows :D

The Darren Shan saga is also a good, fantasy series; though, possibly more for younger teens (I still love them though!)

And of course, the 'Dark Materials' trilogy which has already been mentioned. :D

The series Uglies, Pretties etc is really enjoyable, sci-fi, great teen themes. I really enjoyed them. Have you tried Wolf Brother et al by Michelle Paver? Set in the remote past, just after the last ice age - the first 2/3 are excellent...

Bartimeaus Trilogy - Jonathon Stroud. More sophisticated than Rowling and more humour than Pullman.

And I second Pratchett, The Amazing Maurice and his Educated Rodents might be a good one to start with.

I haven't read them, but my Twilight-reading daughter did love the Maximum Ride books.
Also, perhaps, Megan Whalen Turner's books (start with The Thief)
Sarah Rees Brennan 'Demon's Lexicon'.
My Malorie Blackman reading daughter liked - well not liked, exactly, but devoured Jodi Picoult's 'My sister's keeper' - she made me read it, and it is a good read. She also loved 'The Book Thief' by Marcus Zusak.
I don't know that I've read anyone exactly like Eva Ibbotson, but you could try Mary Stewart, and possibly even Georgette Heyer (try The Grand Sophy, perhaps.)
Off to look up Cherub, which I haven't heard of before...

For fantasy, anything by Diana Wynne-Jones - for Harry Potter fans, particularly the Chrestomancy series.

The Earthsea Quartet by Ursula Le Guinn

I would suggest The demonata series by Darren Shan. It is really good and the first book is called Lord Loss.

I have been waiting for this one for ages now. Due on September 1st, The first in the Pasha series, "Pasha and the Lost Mountain" looks right up your street.
It is available for pre-order on here, I have just ordered one.

I recommend the Wardstone Chronicles by Joseph Delaney. Brilliant for children, and enjoyed by many adults as well!

Trudi canavans books are good I would start with the black magician trilogy

The Denthan Series by Sam Wilding get my thumbs up!
The Magic Scales - book 1 is full of magic, excitment and laughs

P.C Cast - House of Night series - (Marked etc.) very much in theTwilight vein
Diana Wynn Jones - Chrestomancy series (Charmed Life etc) more like Harry Potter, perhaps a little younger
Melissa Marr - Wicked Lovely etc. - definitely older readers - modern faerie
Christopher Paolini - Eragon (Inheritance series) - fantasy magic
David Eddings - Belgariad series (beginning with Pawn of Prophecy) - more fantasy magic
Garth Nix - Sabriel etc. - slightly more sci-fi fantasy magic with female lead
Trudi Canavan - Black Magician series (The Magicians Guild etc.)
Alison Croggan - Pellinor series (The Gift etc.) - more magic
Celia Rees - more in the line of Eva Ibbotson, some historical (Witch Child, Pirates!), some sci fi (The Stone Testament)
Cornelia Funke - not just Inkheart

There's lots out there!

I definitely agree about the wardstone chronicles. This series is also called the Spook's series, and the first one is Spook's apprentice. They are brilliant series that are also very readable and very affordable.

How about Garth Nix - Mister Monday etc series or
Anthony Horowitz - Power of Five series

[Deleted by the author on 23 Jul 2009 20:34 BST]

New book out today - Hattori Hachi: the Revenge of Praying Mantis. Loads of action and a great female lead! Tell your friends - www.hattorihachi.com