Here is where I got my info:
http://www.absinthebuyersguide.com/faq.html#Anchor-14210
And the following are some of the key Q&A's
Why is absinthe not sold in the United States?
Absinthe is not sold in the United States because the U.S. Food and Drug Administration (FDA) does not allow the sales of spirited beverages that contain the chemical compound
thujone. Real absinthe is made using wormwood, which contains thujone.
Can I buy absinthe in the United States?
No.
Can absinthe be shipped (mailed) into the United States?
Absinthe is a "prohibited" item and is subject to being seized by the United States Customs.
Can I make quality absinthe at home?
Producing a quality absinthe requires distillation and experience. If you are fortunate enough to live where home distillation is legal, you can learn to produce quality absinthe.
Owning and operating a distiller, without a license, in many countries, including the United States, is illegal.