Hi Requiem,
Once you acquire it you should only need to change the nameservers to match the server where your hosting account is located here. You would also need to make sure its set up n your account here as either the Primary or an Addon/ Parked domain.
You could should also be able to transfer the domain registration to Lunarpages but you may have to wait as there is usually a 60 restriction on the transfer of newly registered domains from Registrar to Registrar.
Ok, I made an account at NameSecure for the domain switch from the person I'm buying it from. I'm just waiting for it to happen from her end now. Then I'll send a support message to LP and tell them to switch my primary to this new domain name, as well as change the name servers.
If I use NameSecure for the time being, and build my website and it's up and operational, will it be a seemless transition if I switch from registrar to registrar (NameSecure to LP) while my site is live? Meaning that my site won't be offline during the transition?