I downloaded one online, you could do the same if you're really anxious.
I still don't have a formed opinion about Volta as I only listened to it once. As with every Bjork album it sets itself apart from her other workand it's different no doubt about that. Still, I wouldn't say it's as brilliant as Medúlla, imo her best. Like Vespertine, it has 3-4 stand out songs like Wanderlust, Declare Independance, Pneumonia and one of the duets Dull Flame of Desire. The rest is a bit ehish.
This is why I decided to put it a few spots below where I originally had it on my to buy list.