I know that the national club has a web site. Try putting Soft Coated Wheaten in a search engine and you should get it. If memory serves me right...there is a club in Chicago. It seems that there are some health promlems with the breed here in the US so check the breeder carefully.
They are great dogs. I show and breed Irish Wolfhound and a friend and breeder in Ireland has both breeds. I usualy do not care for terriers but I really like the Wheatens.