Registering a domain for a home machine..

I'd like to register a domain name. Basically, I have an IP address that hasn't changed in the last 18 months. In theory, it could change, but it hasn't and won't in the forseeable future. What do you I need to do to register the domain to get a DNS server to point to my IP address? I've looked through register.com, etc. and I'm a bit unclear how to get it to go to my own IP address.

Thanks in advance.

You need a credit card to register a domain name. Costs vary but are relatively inexpensive. The longer you register, the lower the per year cost. I use Stargate Communications for my domain. They provide me with free, but limited DNS services (IIRC 8 records) that I manage myself.