Dumb question. Are all the legs the exact same length?
You can try building some leveling legs by drilling holes in the center of the leg and using a T nut or screw in threads and threaded leveling legs. You can pick this up at your local lumbar store.
Are you sure the floor is flat?
Several things could be causing a table to wobble. The most common issue first off, depending on where the table sits, the floor may be the issue. As for your project, make sure all the legs are cut to exact lengths. If you're off by even a 1/16" you will feel a slight wobble. Another issue may be that something is off square. What ever the issue is, the simple fix is to buy some levelers at your local hardware store.
Need a picture of he table you may need corner blocks need a picture.
Don't be put off by negative replies like Matthew's
from experience I can assure you the "dumbest" question it the one that "Isn't asked"
I hope you have resolved your problem and are making good progress with your table :-)
Matthew's reply was not negative, he was stating that his own question was dumb.
meaning, most likely the legs were the same length but he was asking anyways just to make sure.
One of the slickest videos I've seen recently was the concept of using a table saw with a large table to "even up" chair legs. They basically set the blade height so just the tiniest bit of blade sticks up. Then the place the chair on the table saw so all the feet are supported, select a foot that is a good candidate for trimming, and then they run the foot across the saw sideways - back and forth - checking for stability after each pass.
That got me to thinking about building a torsion box work table - so it is dead nuts flat - and somehow installing a belt sander upside down in one of the table corners ... for the purpose of leveling even large-ish tables.