After working as a PTA treasurer for some time, I have found the following resources essential to have on hand:
The PTA  Money Matters  Guide is put out by the National PTA.  It is an excellent source for all things financial.
The Treasurer's Compass is put out by Non Profit Central and is also an excellent resource for day-to-day operations.
The following are some documents I developed to aid local units in maintaining a proper record book:
Disbursement Form Members will fill this out when requesting funds from your PTA, whether a reimbursement or for payment of an invoice
Request for Advance It is not always feasible for a volunteer to pay up front and then request a reimbursement.  This form is to be used to ask for money in advance.
Deposit Receipt It is essential for proper procedures to take place when counting money.  Use this form to verify 2 counters and amount deposited in the bank.
Task Proposal  This form is an excellent way for Teachers or Parents to ask the PTA to fund a project or purchase.
Tools for use in your end of year audit:
2015-2016 Local Unit Audit Report  These are the forms to fill out and send to State while doing your audit.  Please note that this form has been updated from the ones used previously.  It is longer, but answering it completely will make sure you have the correct moneyhandling procedures in place.  Use the Audit Report Instructions to guide you and please don't hesitate to contact us if you need help! 
Don't forget to pay your Membership Dues! 
Try to do it monthly, but the deadlines are 12/1, 3/1, and 6/30.
2016-2017 Local Unit Dues Remittance Form