where is there a good beginner theravada buddhist weekend retreat in the US or Centra

I want to get more into my Buddhist practice and go from being a "bookstore Buddhist" to someone more enlightened. I'd really like to go to a good retreat in Colorado or California. I also really want Theravada and not Vajrayana, although a combination of meditation and ritual would be cool.

Well Buddha once tried to drown himself, you could try that if you want.

Hi, I'm South American, Argentinean. And I am Buddhist since I have memory. I believe in Mahayana Buddhism, and I also meditate daily. I don't live near you, he he, but if you have any doubt, ask me!
I know a lot and I have read a lot

The Insight meditation tradition is the most common form of Theravada Buddhism taught in Central and North America.

Here is a listing of Insight meditation centers - you can go to the websites of these organizations to learn about their retreats:
http://www.dharma.org/ims/mr_links.html#dharmacenters

If Northern California is convenient for you, then you might consider Spirit Rock Meditation Center north of San Francisco. This is the primary Theravadin center on the West Coast.
http://www.spiritrock.org/

The other common form of Theravada Buddhism taught in North America is Vipassana meditation, with retreats offered by the S.N. Goenka organization. Here's a listing of centers:
http://www.dhamma.org/en/bycountry/na/

Best wishes on your path!