DNS entry changes

Anyone know how to make changes to a DNS server?

Reason I ask: I own a domain (who doesn't :) ), that is being hosted by a company. Since right now I'm only using it for the email and as a quasi storeage space I would really like to move it to my computer (I have all the software to run email and web server). The problem is that I'm on a Dynamic IP for my DSL and for some reason I have to power cycle my modem and router at least once a week (thus getting a new IP). I would really like to be able to make my own changes instead of having to pay someone to do it for me.

I have checked into the services that will do it for you but all I have found require that you subdomain or pay them. And besides I really like knowing how to do stuff myself.

ummm... it takes several hours to a day for changes to propagate through the DNS servers... so that wouldn't be a good choice.

Yea I know the time it takes to for the change to go all the way through and I'm willing to accept that. Hell it might cut down on the amount of spam I get :)

To change the records you must control the nameserver the domain points toward. If its really YOUR domain and not the hosting companys (if you registered it through a registrar, ur good, but if they registered it for you, your screwed) you can change the nameservers it points to. There are free domain name servers for use at zoneedit.com. Happy spamblocking.

In add on to what the previous poster said, look into dynamic DNS to solve the problem with your ever-changing IP address.