I've been reading up on thermoclines wondering how to find them.  I was thinking some sort of digital thermometer that you sink to certain depths and you take a reading, but I can't seem to locate one.

Anyone know where I could find a thermometer like this?

This one is the best on the market for non-technical/routine applications:

http://www.cabelas.com/prod-1/0012329014907a.shtml

If you don't want to drop that much $$ on a unit though, you can get by, albeit somewhat less accurately with any of the digital readout units with a long cord similar to this one, keeping your lakes depth in mind:

http://www.cabelas.com/prod-1/0036368018444a.shtml

-T9

You don't need a thermometer to find the thermocline.  Just turn up the sensitivity on your graph.  It will appear as band between the surface and bottom.

I have a couple of the Minn Kota guages. The best one I have is one made by Vexilar many ,many years ago with the cable color coded at each 1'. It is similar to the ClineFinder. My most usable instrument for finding thermoclines is a LCR sonar unit. I use the temp guage sometimes to discern a thermocline from plankton when I see the layer on the graph.