Good luck. It's the hottest ticket in four years.
http://www.getinaugurationtickets.com/
The Presidential Inauguration will be held on January 20, 2012. A week of festivities will include the Presidential Swearing in Ceremony, Inaugural Address, Inaugural Parade and a night of Inaugural Balls and galas honoring the new President of the United States. The theme for the 2012 presidential has not been decided yet.
You can get tickets through your congressional or senate representatives. To find out who your representative is go to the Inauguration Information page and click on the appropriate links.
Tickets to the 57th Inaugural Ceremonies will be provided free of charge and distributed through Members of the 111th Congress. The Joint Congressional Committee on Inaugural Ceremonies does not provide tickets to the public. Members of the public interested in attending the Inaugural Ceremonies should contact their Member of Congress or U.S. Senators to request tickets. The public should also be aware that no website or other ticket outlet actually has inaugural swearing-in tickets to sell, regardless of what they may claim. Tickets will not be distributed to Congressional offices until the week before the inauguration and will require in-person pick-up.