Im not sure whether or not the local lake has smallies.  Its known as one of the better largemouth lakes in KY, but its in a private, gated neighborhood called Doe Valley, so not many people fish it.  It is fed by several creeks, deep, (fairly)clear,  rocky, and stays cooler for most of the year because of underground streams.  It is full of shad and crawfish alike, which makes me think there should also be smallmouth, but I have never happened across any while largemouth fishing.  

What are some good techniques/lures that I can use to search out smallies on my next trip, but also still catch some LMB?  If there are no smallies I dont want to waste an entire trip.

Smallmouth will attack the same lures as largemouth. If there are any in the lake you should occasionally catch one. As a specific recommendation, try a 3 1/2" Mizmo tube, Kent's Classic (squash green). Focus on rocky structure off the shoreline, in deeper water.

The Fat Ika is another soft plastic that works well for both species.