I tried to Google, but with safe search on, Google wouldn't search on dixie.chicks. I know Maines husband is Iranian, but I thought one of the others had an islamic husband or boyfriend as well.
Just go to the IMDb and search on Natalie Maines. Her husband is an American of Iranian descent. The other Chicks are linked from her bio, and their husbands don't seem to be Muslim, but it's not specified.
Natalie's husband, from imdb.com
Adrian Pasdar was born in Pittsfield, Massachusetts, but at the age of 2, his father, a prominent heart surgeon, moved the family to Powelton, Pennsylvania, a suburb of Philadelphia.