After I posted my first post about invalid click - regarding the "adsense pirate" email that I got, I now see that about $2 and some change was deducted from my adsense earnings because of invalid clicks.
It worries me though in case adsense might consider disabling my account although I have gotten a response from someone here who says that Adsense deals with this kind of thing all the time!
The solutions that adsense provides for helping to stop invalid clicks seems so complicated and its so hard to find PHYSICAL contact information for Adsense - meaning a telephone number!