Also, if you want to pursue Clapton in particular, there is the "Bluesbreakers with Eric Clapton" album. The Amazon summary says: "Apart from being one of the most overall influential albums in Blues-Rock history, it was likely the first time anyone had heard a Gibson Les Paul guitar through an overdriven Marshall amplifier; this unique sound would become particularly influential." An Amazon commenter says that the 2009 2-CD version is saturated, but that the 2001 reissue has great sound.
And there is also "Layla & Other Love Songs" by Derek & The Dominos, with the dream pairing of Clapton and Duane Allman. This is one the rock end of the spectrum but there are several fine blues numbers on it. There is a 40th Anniversary edition with additional tracks.