Nick Hornby (of High Fidelity, About a Boy etc fame) is the author of the novel which this movie is based on.

It's called "Juliet, Naked" and the frame of the story is about a guy, who has a website dedicated to a musician with a very limited output 20+ years ago... ring any bells - cough ;-)

Various hilarity ensues as a demo of his most famous recording resurfaces and the guys girlfriend accidentally begins an email romance with the musician. Pretty cute Rom-com movie, if you are in that mood.