Apple's Quicktime has the Speed Racer trailer online and the official Speed Racer movie site has a download option.
You can download free the Speed Racer Movie trailer at the official Speed website. It has the HD options to view or download. Speed Racer stars Emile Hirsch, Christina Ricci, John Goodman, Susan Sarandon, and Matthew Fox. The movie hits theaters on May 9th, 2008.