try arin's whois query page to search the IP address of the email sender. You should be able to find out EXACTLY who it is. I would also get yahoo's help.

here's the link for the query: ws.arin.net/whois/?queryinput=

Why push reply to any email received in anonymous fashion?
you have no idea who is behind it.
directoreis can also be lost or stolen.
by pushing reply to an anonymous email, you are tagging your email address as 'valid' and you might get further unwanted messages from the same, or another, source to where your address has been forwarded.
also, messages (ie your reply msg) themselves can easily be manipulated and misused.

CC has it right, imo: just leave it alone.

The disclaimer is a good idea but not a cure-all. Once this type of contact information is printed and distributed, you have no control over how it's used.

It would be more helpful if the distributor of the messages identified themselves. Leaving it up to speculation irresponsibly targets the PTO and, in my opinion, lessens the message.

I'd say leave it alone. If you followed best practices you are not resposible for how the final product is used.

sounds like the intent of the communicaiotn was good - to inform (going the anonymous route, however, is a bit odd) - and nothing malicious, or wasnt for personal gain or such (ie commercial type spam) which is why lots of these school directories have the disclaimer lieke 'not to be used for commercial purposes'.

The end justifies the means - credited to Machiavelli.
I don't adhere to the above statement but in this case, it might be valid. This person is bringing to light a situation that should be exposed. Does it matter how he/she has chosen to get the word out? I am not saying that I agree with this persons tactics or the fact that they are hiding behind an anonymous e-mail address. It sounds like they are trying to raise parental awareness about a potentially underhanded situation.

Your directory has a disclaimer in it, so the PTO is absent malice. You have taken the situation head on, given the person alternatives and they have chosen not to heed your advise. You have done everything right so let the chips fall where they may.
Good luck.

Is the PTO even under the provence of the school district's legal dept.? you asked.

dont know, but you label it in your last post the 'shcool directory' from which the addresses were presumed taken, not the 'PTO directory', hence it is not a propreitary dierectory and therefore a matter for the shcool to give advice on, if the practice continues even after you have wisely repsonded to the mailer with your psition.

the way you handled theunwanted mail was perfect,btw. imo