You can find many post in the forum and some listed below with mutiple sites. Sometimes the cheapest price is not the best.
GoDaddy has the lowest .info I have ever seen. If you want a free domain name head over to namepros.com
Dizzen ... RCJ is 100% right. Being a domainer myself and having worked for a top registrar ...price is not the end all be all. Register from a company that will support you, not just during the sale, but after the sale as well. In addition, look at security and the steps taken to protect your virtual real estate. I would personally recommend Moniker, but take a look around and compare. -=Chipmunk=-
Besides godaddy, you can try dynadot.com make sure you check the renewal domain price because that's where they tend to hide the "catch"
OneAndOne.com used to be cheap. They got behind now. Also their control panel is the worst I ever seen. GoDaddy is most reliable and consistent from my experience.
Hi Its the one with less price but I really dont recommend you for the cheap option. Remember that Quality and Quantity both matters
GoDaddy may be the cheapest but I still like NameCheap. I have about 20 domains with them but only one .info domain. I think they are now $4.88 there but they have great customer service.
Maydomain.com is under dotster.. the coupon "bargaincat.com" will save you 15% @ dotster. also this will get you .info's at 1.03$