Can anyone recommend a good one?
Few of the popular reseller domain name registration services include:
Dotster.com (totally brandable)
OnlineNic.com (Requires you to pre-pay US$80)
iDirect.com (They also require you to pay a small pre-paid amount)
Can't remember anymore at this time
Directi.com has an excellent reseller program.
Pricing is around $7 per domain.
Their api is pretty simple to integrate & they will be releasing a comprehensive billing module soon.
You sell domains for any price you want, as long as its more than $9, for thats there cut of each sale. Completely brandable. Not sure about residual renewals.
It's not who I am underneath, but what I do that defines me.