1st thing, I want to thank you for being so respectful to the land owners. It means a lot to so many people on here to have that kind of respect.
2nd, I would take a drive and walk around the place a little bit and see if there are any signs. This may help you. If you cannot locate any signs, knocking on a few doors never hurt. You may make some new friends and get answers to what you seek.
In some cases you can find info on the ponds with your county if it's legal to fish or not.