Unless you're doing this as a learning exercise, I'd highly recommend that you have someone else handle your dns for you. This is esp. true if you decide to handle email services yourself, as not going without email for days because you hosed your dns can be VERY frustrating.
If you don't have a static ip then you can go with a service such as dyndns.org. They provide scripts for various os's that will automatically update your dns entries with whatever ip address you get assigned. Some routers (Netgear) actually have support for dyndns built into them.
If you do have a static ip, then you can go with someone like google, they charge 15 a year to provide various services including dns. This route is very convenient because you also get their email services (they host the smtp and pop servers) and I guarantee that my time is worth much more than $15 year.
In either case, you go over to network solutions, log into your account, and change the dns servers that you have registered for your domain to either dyndns.org or google.com (or whoever you chose to handle the dns). Keep in mind that if you do your own dns servers, you will have to make sure your dns machine stays up all the time, or things like email will fail (i.e. if someone tries to send you an email, even if you aren't hosting your own smtp server, your dns server won't be there for the sender to find your MX record to know which machine to send the email to). Now you might get lucky and the sender might have your ip address's cached, but you see how problematic hosting your own dns can be.
If you really want to try it yourself, I would highly recommend that you still use some other dns servers to act as your secondaries, again so if anything bad happens to your dns server, there will be others to fall back on.
If your just tinkering on a domain that is just for play, then go for it. Have fun with bind, you'll learn to love nslookup. Interestingly, this is one area that Win2K shines in, setting up a dns server is mucho simple.