I just came across this question and thought I'd respond, in case it is still useful.
Since JMP 11, you can turn on the labels for a bar chart in Graph Builder by using the label option in the Bar panel located to the left of the graph. Create your bar graph in Graph Builder. Then, to the left of the graph under the Bar properties you will see an option for labels. You can set the labels to be by value as well as a few other options.