Kevin Costner's estranged wife, Christine Baumgartner, opted for a little retail therapy amid her divorce, and she was spotted doing so without her wedding ring.Baumgartner went out and did a little shopping on Thursday in Santa Barbara, California, which is not too far from the home she and the star share in nearby Montecito. Baumgartner looked quite fashionable with a white fedora hat, denim jacket, white top, jeans and matching white kicks.The outing comes less than a week after Baumgartner filed for divorce after more than 18 years of marriage.