Undiscovered blues gems.....

Boy, I'm going to pick up a few of these with Peter Green The Splinter Group being the first.
You probably have this one but I believe Jimmy Rogers' last recording, Blue Bird, is a must have. I also believe his son, Jimmy d Lane is among the best today (what electric guitar work). His latest, IT'S TIME, always sounds incredibly good to me (I have the SACD version). Double Trouble performs great in backing up Lane.

While your at the store, pick up any of Doug MacLeod's albums. Incredible acoustic guitar player. I'm assuming from your post that you already have all the usual suspects, Hopkins, Waters, Sonny Terry, etc., and are looking for more recent artists. A absolute must have is Mary Gauthier. She's the real deal, not someone that is just singing and playing the blues, she lived them and you can hear it. One of her more simple songs is called "I Drink", and when she sings it you know it is from experience.

As far as more recent recommendations, if you are into the mouth harp, William Clarke was a fantastic harmonica player on the LA circuit (who unfortunately passed away somewhat recently). In particular, I recommend Serious Intentions and Blowin Like Hell (both on Alligator Records). Also, although they've gotten some coverage in high end magazines, the North Mississippi All Stars are probably the most fun blues band I've heard in the last few years (both Shake Hands with Shorty and Highway 51 on Tone-Cool records are a blast). Finally, if you are looking for "audiophile quality" recordings, any blues on Audioquest (particularly Robert Lucas) and Analogue Productions (Jimmy D. Lane, Big Daddy Hypolite) would be worth a look.

Ronnie Earl & the Broadcasters - 'Blues Guitar Virtuoso Live in Europe'

just got turned onto Howlin Wolfs chess records box set. way cool