I have a cursor on a Waveform Graph that is at a specific data point in the data set and I want to see the value at that point of the cursor. I see that there are many property nodes available for cursors, but which one should I use to get the value that the cursor is currently at?

There is not a single property for cursors on a graph that will get the data value at the current position. Instead, the best way would be to use two different property nodes for the cursor. To do this programmatically, creating a Cursor Plot property node allows you to control which plot your cursor is on and then using the Cursor Index property node allows you to read what index in the data set your cursor is at. The final step will just involve indexing the array of data that is plotted on the graph to get that specific value. The image below shows this process.