If you look at those IP addresses, you'll see that they are all over the place. The Hacker, BotNet, or Spammer that's perpetrating the attacks is using Proxy Servers. They are very likely untraceable, and the proxy'd addresses, which can be 3-5 servers deep, will change constantly. The St. Louis lookup for that address is "Hosting Solutions International, Inc." International Hosting = Hiding one's identity from the Internet World.
Hackers never do their nasty work through their actual Internet Provider without using proxy servers or they'd be caught immediately.
They should be shot on sight, and Proxy server provisioning should be illegal.
-az-