The BBC website has all the information on book related radio and TV programmes, and is particularly useful for budding writers and poets. Fantastic Fiction lists books by series, very handy if you're unsure of the order in which a series runs. Whichbook will help you find something to read depending on your mood, and the Poetry Society website gives details of poetry news and events.
Reader2Reader is a site specifically for public libraries and is full of book reviews submitted by readers - very useful for getting reading ideas. Similarly, the online directory at New Books Mag holds over 1000 reviews by readers and reading groups. Finally, Reading Group Guides and Book Group Info are aimed specifically at reading groups, with reviews and reading guides.