We had a Paleo Field Trip to Black Cat Mountain in Clarita, Oklahoma on Saturday, April 15, 2017.
Below are some excerpts from the trip email.
Black Cat Mountain yields up some pretty awesome Devonian age trilobites. Google it. George P. Hansen wrote a book and has a nice Web site on the subject. Brachiopods, coral, and a few other fossils can also be found.

Clarita is a long drive (about 6 hours or so from southwest Houston), so you may want to leave on Friday and find a place to stay in one of the nearby Oklahoma small towns or in Sherman/Dennison, TX. and drive the rest of the way Saturday morning. Clarita is a 1-horse town. No hotel.

There are real hazards here from very large diamondback rattlesnakes, scorpions, spiders–plus jagged rocks and possibly heat and sun, depending on the weather. The “facilities” are in the trees, so you will need to pay attention to your surroundings.

Some trilobites can be found loose or on the surface of some rocks, but the really good ones require breaking rocks apart, looking for the cross-section, and prepping the specimen out later.