There's an olive oil tasting bar at Fairway Markets here in the city, and I'm enjoying working my way through their store-bottled assortment. Off the top of my head--they have oils from several regions in Italy, Spain, Greece, France, California, and Australia. For a while I was buying a nice peppery oil from Puglia, but I think my current oil is Spanish. The oils are sold in 1-liter bottles, and I decant a liter to share with my significant other. We refrigerate most of the oil so it doesn't go rancid if it's around for more than a couple of months.

A while ago I tried a California oil from Trader Joe but wasn't terribly impressed.