More improvising, 36 bars in A and Bb blues scales last week. What is the blues scale? 1, 3b, 4, 5b,5 7b. The minor pentatonic will also work (which is basically the same as the blues scale but without the 5b). If you play these patterns over the chords (major chords) it should fit well. We have also been playing modes i.e changing the scale depending on the chords and flattening the 6th.
Learned a sort of blues rhythm/chop from Darol Anger and Richard Greene on YouTube - both great blues fiddlers. I've also been playing and listening to the Blue Reel by the wonderful late Oliver Shroer.
Read about the "blue devils" (basically being in a miserable and depressed state) in Oxford music online. Visited the local library and borrowed "The Illustrated Encyclopedia of Jazz and Blues". Its a great round up with internet links and unusually gives an A-Z of contemporary artists (post 2000).
Chord progressions in 12 bar blues are often I, IV, V progressions. We have also been exploring slightly more complex patterns based on II, V progressions - which gives more of a jazzy sound.