Personally, I use RegisterFly.com. The domains are $10 or so, and I prefer them because I can pay PayPal. Nice management system too, I have around 10 domains there and they are smooth as a babies bottom (smells better too).
I am also an enom reseller and have been very happy with them, too. They have many free domain features, such as email forwarding (you can specify individual addresses!), URL forwarding, website builder, etc..
Many other registrars will charge you extra for this. And they have good prices.
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