Best Place to Register a Domain Name, Opinions Wanted

I understand there are several places (web sites) to see if a domain name is
available and if it is, to buy (lease, pay for, whatever) it.

Does anyone have an opinion as to the best (cheapest) one given that I don't
need then to host the site?

Does anyone have an opinion as to the best (cheapest) one given the
possibility that I might need then to host the site?

Thanks,

George Wayne Gambill ... Registered Linux User: #311028