Watch the Lazy Freeway: Rhythm online guitar lesson by Jeff McErlain from Blues-Rock Evolution
When it comes to tone I am mostly a Marshall guy. To me, they define the blues rock guitar sound, starting with Eric Clapton's tone on John Mayall's Bluesbreakers record. Guitar geeks call Clapton's sound on that record the "Beano" tone, a reference to the comic book he's holding on the cover.
Clapton was one of the first to play a Les Paul through a Marshall JTM45 2x12 combo amp and turn it to 10, pushing the amp to the point of aggressive distortion and feedback.