I dont know what it cost, but I do know some of what it took for Obama to go to Denmark.
The Secret Service sends an advance team over about 1 week in advance, scouting out airports, the route Obama would take, the meeting place, and every other place Obama would be.
They also have a team there to secure the fuel facilities for all of the POTUS's aircraft and vehicles.
They take at least 2 aircraft, AF! and another plane carrying the presidential limo and his helicopter, along with other needed vehicles.
The President also takes his staff, national security people, chefs to prepare his food, etc.
I did find this...http://www.boingboing.net/2007/11/29/president-bushs-trav.html
Its dated info, but there is no reason to think that Obama travels with any less people.