Few things before you do..
1. Make sure you go to the eye doctor and get your exact prescription. You don't wanna get something that makes it so you can't see..
2. Check out PinkyParadise:
http://www.pinkyparadise.com/So far, these are the only circle lenses I've heard of that you get your prescription type for. But when you go to the eye doctor, make sure you can even WEAR them first..Some peoples eyes are not right for them and it can be very painful and bad if you get them and you aren't suppose to be using them.
3. Circle lenses are technically Illigal, but there was a thread on cosplay.com where people showed that the FDA equivalent over there has approved them and the US just doesn't wanna go through the papers to make them stamped "OK" here..Or something like that..lolPlenty of people say they are safe. Don't skimp on price just because you think cheaper is a good thing. Cheaper are that way for a reason. If they don't even ask for prescription, there's a huge chance they are crap and will ruin your eyes even more.