I personally can't fathom the idea of buying/adopting a living creature without researching it first. I'm always paranoid that I'm impulse buying, and researching gives me time to decide if I'm really serious about my decision to get an animal. Plus, every time I've done research on something, I've learned something important that I never would have realized before (such as Guinea Pigs need lots of room, mice can't have any fabric other than fleece and felt, Gerbils are borrowers and LOVE having their tank half full of substrate, etc.) I researched before getting each fish, too (they don't all get along, and they all have their different difficulty levels)
It's not too hard to come across an animal in a store or in a friend's house and GO BACK HOME to read up a little on it before making any rash decisions. It might be a little more inconvenient with cost of gas or the time out of your day, but better you than the animal in question, right?
I always get a little sad when I come across someone who has an animal that they're CLEARLY not caring for properly (pine shavings for little guys, though I personally don't like it for piggies either), or junk food for cats/dogs, or little "Starter Kits" for animals that will clearly outgrow it or chew it to bits. Practically everyone has the internet nowadays. Google is your friend.