Don't get me wrong though; I know it's aggravating to sit back and do nothing. I'm just trying to save you some frustration.

I mean, imagine this:
Some guy spoofs his laptop's MAC (using SMAC), then daisy-chains through various non-logging proxies (google "free proxies") from his car where he's leeching off of random unsecured hot spots (easily found with NetStumbler). Now even if you managed to somehow find the actual originating IP that tunneled through the proxies, you'd be going after the wrong (possibly unknowing) person whose router logs will yield nothing more than a fake MAC and some other trivial information. Still want to try and find this guy?

And this is just one situation of many possible situations. Chalk it up to experience and be happy your firewall works the way it's supposed to.