There are a fair few literary festivals happening this time of year:
The London Book Fair ("the global publishing community’s leading Spring forum for bookseller, publisher and librarian buyers and specifiers worldwide") is running March 5-7th. The LBF is a trade show, so not nearly as interesting as it thinks it is.
Bath has: The Bath Shakespeare Festival (March 6-19th) and The Bath Literature Festival (March 4-12th).
Keswick, in the Lake District, has: Words by the Water (organised by Ways With Words) (March 10-19th). I'm fairly sure, RSB interviewee Michael Schmidt is talking at some point during this event ...
Then there is the Oundle Festival of Literature (March 4-18th). The line-up includes PD James, Polly Toynbee, Sir Roy Strong, Anthony Horowitz, Louis de Bernieres and the Antonius Players, George Alagiah, Michael and Rebecca Frayn in conversation with Maya Jaggi, Wendy Cope and Joanna Trollope. I shall not be attending!