I thought I would just pick a domain name, register it then I would be done with it. It appears that it is more involved than that. I have found a host for my site, do I need to register the domain before or after I set up my account with them? If I pick a domain now, can I pick another 6 months from now and start using that one? Why would I need an e-mail account with my domain registrar? What is there to "manage" with a domain name? Thanks for all the help.

You will need a domain name eventually for your website - but you can get the domain name first or the hosting provider first it does not matter.

As for buying another domain later and using it, what specifically do you mean - pointing the second domain at the first website? Switching to the second domain and dumping the first? Setting up a second website? I don't understand the question.

As to why you need an email address to register a domain name, the admin email address controls the "fate" of the domain. If your registrar needs to contact you for renewals or transfer verification, they use the admin email. If you don't have a valid admin email account on your domain, you risk losing it to a hostile transfer attempt, missing a renewal, etc.

Hope this helps.

-t