Yes, you can find the thermocline depth with a remote temp sensor thermometer. I use one to verify what looks like a thermocline on my electronics (plankton will look like the thermocline sometimes).
As far as presentations, any slow falling plastic lures will work great. You just have to be patient enough to use them in the whole water column. I caught 41 bass there yesterday and the most productive presentation was my avatar.
For productive locations, the prominent bottom features are the key to finding were they are (steep drops like creek channel edges and points are the most prominent). Finding those without electronics is as easy as paying attention to how long it takes a weighted lure (Tx. Rig or jig)to hit the bottom with several casts in a fan pattern.
For a hint of the thermocline in the summer, leave a jig or Tx rig on the bottom for about 30 seconds when you throw into what seems like deep water. When you reel it in, feel the lure, and if it feels cold, you are fishing too deep. Below the thermocline the water temp is in the 50's when the surface water temp is higher than about 85 degrees. A thermometer is an inexpensive instrument that will give you an idea of what is going on below.