FIRST IN FASHION: Speaking of first ladies, stylish women know that if they like the look of something, they better get their hands on it quickly before it sells out. Case in point: First Lady Michelle Obama. Isaac Mizrahi’s first Liz Claiborne collection just hit stores and, on Thursday, she was spotted wearing a white ruffle Liz Claiborne New York blouse while visiting Miriam’s Soup Kitchen near the White House. She teamed the look with a pink cardigan, black pants and a Sonia Rykiel plastic belt. Obama is wearing the same belt on the April cover of O, The Oprah Magazine, where she uses it to accessorize a Michael Kors dress and Dear Cashmere cardigan. “She has an amazing proportion and anything she wears takes on the Michelle Obama mystique,” Mizrahi said.