IP Blocking or viewing

Is there any way it look at the users IP? And to Ban them by IP?  I have been getting the same guy creating lots of accounts and spamming then I ban him delet the post one at a time and he comes back with more the next day? Some kind of IP control and or blocking would be nice.

I just opend the site I can see a huge problem with this if it ever starts getting more hits than just the one spammer..

Thnaks