LOL! I thought you could only get tickets from a member of congress after 9/11 these days?
I can truthfully say it was the most overrated tour in DC. Large tour groups, National Park Service employees who pulled the group from the front and herded them from behind. 30 minutes or less from start to finish and, unless you were fairly tall as I am, most of what you saw was in cracks between the mass of humanity filing through.
We got a private tour of the capital via tickets through our DC Representative which was at least 10 times as impressive with a less than quarter sized crowd.