If you need email notification then I don't have any other pointers, but if you just want a domain name to resolve to the correct IP address as that IP address gets changed, then the dnsupdate.org client has done well by me.

I have used the client http://www.dnsupdate.org/ to update a DNS listing at zoneedit.com for my domain over a number of years. zoneedit.com does free dns listing for a few domains before you need to kick them some bucks. Once installed configured to use zoneedit.com the dnsupdate daemon magically gave laptop.example.com the correct 192.168.1.xxx address automatically, with no need for any further work. I found that easier than having to deal with email messages.

I haven't set up anything at dyndns.org for a while (my last email to or from them seems to be dated in 2003), so maybe it has gotten more difficult to make use of their free services without having to say "no thanks" to all of their paid services. Using zoneedit (or other providers?) means you need not deal with dyndns.org at all, but I also haven't opened a new zoneedit account in years (though I continue to use them for some DNS services) - I don't know how onerous their current signup procedure is.