with some of them - certainly not with OneandOne, with whom I have a business account. They will register domain names quickly and inexpensively, and I can recommend their hosting service.
One of the problems sometimes associated with very cheap domain registrars is that it's extremely difficult to get them to part with the name, should you want to move it to a different name server. They want you to pay for additional services, once they have you safely on board with a parked domain name. Go for a reputable company like Oneandone and you'll noty go far wrong.