I found a great website with photos and soundtracks of our native frogs and toads, which actually have no scientific differences. It's at: http://www.tpwd.state.tx.us
Unfortunately, I've spent 20 minutes trying to get this really long link online here for you and it keeps messing up and won't wrap the text in my post without losing letters. So, you'll have to search in the Texas Parks and Wildlife website -- so sorry.... but it's well worth it!!!
I'll probably still refer to the dumpy brown ones as toads and the shiny green ones as frogs!