DOWNLOAD: Robert Plant & Alison Krauss and George Thororogood star on Rounder sampler

That most legendary of American independent labels, Rounder Records, celebrates its 45th birthday with a seriously choice 15-track sampler featuring the likes of Robert Plant & Alison Krauss, George Thorogood & The Delaware, Blackberry Smoke, Pokey LaFarge, Clarence Gatemouth Brown, Steve Martin & Edie Brickell, Nanci Griffith and Norman Blake. Americana, folk, blues, R&B, soul, rock, country... it's all on the Nashville/Boston imprint's musical menu. The collection's free but don't be shy about tipping!