I believe Burley trailers are still made in the U.S.A.
EDIT: Per their website, Burley trailers are made in China and the Philippines.
Try CycleTote (www.cycletote.com) or Chariot (www.chariotcarriers.com). Both are a little expensive, but look to be much higher quality than your standard Wal-Mart Chinese garbage.
Carlisle trailer tires are made by Carlisle Transportation Products. The company is am American company with all products being made in the USA.
Trailer Made - 2010 Time Capsule - 1.11 was released on: USA: 16 May 2011
Trailer Made - 2010 Lockjaw 1-6 was released on: USA: 30 January 2011
Trailer Made - 2010 Jesus Freak 1-3 was released on: USA: 22 November 2010
Trailer Made - 2010 Time Capsule 1-11 was released on: USA: 16 May 2011
Trailer Made - 2010 Tin Dreams 1-1 was released on: USA: 1 November 2010
Trailer Made - 2010 The Case of the Narcoleptic Vagina 1-5 was released on: USA: 17 January 2011
Trailer Made - 2010 Your Children Need to Be Cleansed 1-12 was released on: USA: 30 May 2011
You can find custom bike parts online on websites like Jenson USA, Competitive Cyclist, and Chain Reaction Cycles.
Trailer Made - 2010 A Whole New Mary Lou 1-8 was released on: USA: 14 March 2011
A trailer.
One can find information about dirt bike racing on sites such as Motorcycle-USA, The MSF DirtBike School, Motocross Tracks and Dirt Rider. One can also find information in magazines such as Dirt Bike Magazine and Motocross Action Magazine.