Oprah Winfrey has topped the first Forbes magazine Richest Women Entertainers List. The big business publication estimates the media mogul has made a staggering $1.5 billion in her career as a newscaster, talk show host, publisher and actress. Winfrey tops Harry Potter author Jk Rowling, who comes in second with a $1 billion fortune, while US lifestyle queen Martha Stewart rounds out the top three with $638 million (GBP327 million). Madonna ranks fourth on the new list, followed by Celine Dion, Mariah Carey, Janet Jackson, Julia Roberts, Jennifer Lopez and Jennifer Aniston.