Rob - why not start by reading All Music Guide to the Blues: The Definitive Guide to the Blues - around £13 on Amazon. It's a pretty good guide to the music.

There's a wide variety of styles. To me, the great thing about the blues is the simplicity and beauty of the musical structures. It invites you in. There's something for everyone who wants to make music and use those structures. I couldn't and wouldn't attempt to sing much of it - after all, what does a white lad from Lancashire have in common with Robert Johnson - but the musical form is still open.

Mind you, I do recall, many years ago, seeing two wonderful old blues men from the Irwell Delta near Manchester - Blind Lemon Clegg and Sleepy John Arkwright (thank you, Mike Harding).

Sorry - memory laps - it wasn't Sleepy John Arkwright, it was Rev. Gary Davis at the Free Trades Hall in 1964. One of the most wonderful nights of my life.