Well there is always Godaddy with a coupon, Mydomain.com offer good prices with the "bargaincat.com" coupon to get 15% off or you have Name.com that also seem popular with some for reasonable prices.
if you sign in at godaddy and put a domain in ur cart then dont checkout and just sign out...they sometimes send you a 10% off coupon to ur email. they did that for me a couple times
Godaddy can sell you one at $6.95 with a coupon. Register.com is giving them free atm. http://www.register.com/promo/acquisitions_8772090537.rcmx?trkID=SEMJ78Vw4W