Spinebreakers

Penguin UK has a site by and for teenage readers - Spinebreakers.  While some of the content is UK-specific (eg. local events), there are author interviews, tips for teenage writers, and so forth, which are of use to those overseas.  Content includes written, audio and video. 

From their About Us page:

Spinebreakers.co.uk is Penguin's pioneering online book community for teenagers, run by teenagers themselves. Editorial control of the site is in the hands of a core editorial team of nine teenagers aged between 13 and 18 years, supported by a large network of contributing teen editors from across the UK.


Working with journalists, authors, editors and web designers, the teen team will produce a wide variety of multi-media content including video and audio reviews, alternative book jackets and endings, soundtracks, author interviews, podcasts, blogs, short stories and much more.

Spinebreakers.co.uk launched in September 2007 and is the UK’s first online book community for teenagers, giving them the opportunity to discuss, debate and interact with Penguin’s rich source of publishing from contemporary titles such as Meg Rosoff’s Just in Case, Nick Hornby’s first book for teenagers Slam, Eric Schlosser’s Fast Food Nation to classics such as J.D Salinger’s Catcher in the Rye and Jack Kerouac’s On the Road.
 
Penguin Australia has The Squawk, a e-newsletter for up to 13 years, and Between the Lines for teenagers (but not, from the looks, by teenagers as per Spinebreakers).

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