The best place to get official logos and how to use them is from the National PTA website. http://www.pta.org/branding
Here is a link to the official zip files PTA Logos (EPS and TIFs in zip file) you must unzip it and you can use them to make logos with your local unit.
Here is a link to the official guidelines Guidelines for Using PTA Logos Please read this before you build you unit logo.
Here is a link to how to customize a logo for your PTA/PTSA Customizing PTA Logos
Here are some that I made. I used Microsoft Word and the free program Paint. If you need help making you unit logo email Rick Godke email@example.com
Here are some logos I use in presentations.