enom
Enom is great, I like them way more than GoDaddy
the reselling can be a bit of pain when you get into the API's and whatnot
You can use their script as the above posts implies, but with that you pretty much need to use their processing and prices become not so good to resell..
If you are selling domains with your hosting, modernbill has a good enom plugin that allows you to use your reseller account and your own merchant account or paypal whatever.... thats a pretty simple and easiest way to get started if you would ask me.
you can get a $8.95 reseller account anywhere for free for enom.
you have to pay in $100 minimum increments into your account
you can find cheaper enom accounts such as $6.95 on ebay for a few hundred bucks, if you have lots of domains, might not be a bad investment.
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