I was in similar situaion at Lunarpages. I just started hosting with them and had domains hosted along with 2 domains registered.
You can host at one company and leave the domain registrations at another. All that is required is proper Name Server pointing ( eg ns1.dreamhost.com ) (there are 3 BTW)
One other misconception I had, and tech support here at DreamHost cleared this up for me, is that I can host a domain here EVEN THROUGH IT IS REGISTERED AT ANOTHER HOST/COMANY, and all I have to do is wait for the 60 days "BEFORE" I do a domain name transfer. Right now, there is nothing hosted at Lunarpages, and they only have the registration of the one domain and the renewal of my wife's domain. I have to wait 60 days to transfer the domain registration (NOT HOSTING) to another company. I have used ipowerweb for domain registrations, as they are fairly cheep, but I have control on Name Servers changes, Domain Locking, Contact information, etc etc. And, since most of the other domains are there, I will simply wait for the 60 days and do a domain transfer over to them. Then go in and make sure the name server pointing is at dreamhost, and not at ipowerweb.
Billing at iPowerWeb told me it is very common for one to host at one company, yet have their domains registered at another company. Both LP and ipowerweb use tuwcows, Inc for the domain registrar, with one difference. with ipowerweb I can go in and enable/diable the lock on the domain. Not so with Lunarpages. I have to conatct tech support to have them disable the locks on the 2 domains I have registerd there. That will soon change S
Hope this bit of info helps. Welcome to DreamHost!
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