No Doubt - Oh I will always remember it so, so vividly

Christmas 2007. I had just gotten the original iPhone, so at the time the fact that I could buy music on the mobile iTunes store and have it download RIGHT TO MY PHONE! seemed so revolutionary

A relative gave me an iTunes giftcard so I rushed to redeem it and try out the store... and I always had liked No Doubt's singles, so I just decided on a whim to buy Tragic Kingdom. What kind of life-changing decision

By the end of the night I had purchased their entire discography and basically gone to heaven and back five times over.
Björk and Fiona Apple - Found old CDs in my parents' collections, ended up loving them.
Gaga and Jack Johnson - I've been a fan since their debut albums dropped.