Salome is right: Saida doesn't sell her DVDs outside Argentina. However there's one particular DVD (Bellydance instructivo) that she made along with Mario Kirlis that you can find, from time to time, on ebay. The seller is musicshop780. I got my copy from him and dealing with him is a breeze. I published a review on the old Spanish forum. Basically, it's a two disc set. The first one is about rhythms and second about a choreography and some performance. I really like that DVD a lot, but I know some people don't like her style. If you like her, you'll like this DVD.
I like Saida's style very much
Does she speak English? I saw some of her instruction video in spanish
I wonder whether she can conduct workshop in English?
If you can make it she is scheduled to do a workshop in september for the Miami Belly Dance convention.
you can do a search and check their website