Unless you are coming out with a porcelain bathroom product for people who ate too many Fig Newtons, I would have to assume you are playing off the partial name of Olivia Newton-John. With no other use than a fan site, you can't really (ethically/legally) make money off of it, so...
$50
BTW, any automated appraisal service will factor in a celebrity name keyword, but won't factor in the limitations on use for profit or lack of alternate uses. I hope you didn't buy it based on the $5k appraisal bot.