Flea Beetle On Tomato

You are probaly correct, the damage looks alot like flea beetle damage. If you haven’t seen the insects it is possible its something else causing this, so we recommend inspecting your plants regularly and at differnt times of the day, as some pests are nocturnal feeders (or early/late in the day). Keep the plant healthy with proper watering, fertilizing as necessary (especially at flowering and fruit set), and good air circulation in/around the plant. If you haven’t staked/caged the plant yet, we recommend you do that now to avoid causing damage later on that could expose the plant to disease and insect damage thru wounding. Here’s a link about flea beetle.
http://www.ipm.ucdavis.edu/PMG/GARDEN/VEGES/PESTS/fleabeetles.html