Ideally, every board member should have a copy of the by-laws. Minimally, the president or secretary should have them. If you strike out there, try the school principal and/or track down former board members to see if they have a copy.
Who would have the by-laws? The secretary? It had always been a voting PTO with motions, etc. I am an active board member and company officer for the company I work for and the PTO meetings are not handled at all like a meeting. Its a totally one sided forum of announcements to parents with no motions, adjournments, discussions, etc. No minutes are taken or at least they are not in the book for any type of other meetings held by the board where they have voted on anything. Well for that matter, no minutes are in there period.
Check the PTO's by-laws. It's possible that either the general membership never did have the right to vote and it was allowed by the board and/or that the by-laws have been amended to reserve voting rights by the board members only.
Our local elementary PTO has stopped letting the PTO members actually vote at all. It's more of a information meeting where they tell us where the funds will be spent. How can they do this? It use to be that you had to pay a dollar to vote and now this year you don't vote at all.
It depends on your by-laws. In some organizations, the by-laws allow the president to vote and not in others. In still other organizations, the president is allowed to vote only in the event of a tie. Check your by-laws.