JJohnson, that cover of Erin is excellent.
My favorites aren't lesser-known... and are, quite frankly, mainstream... but here are a few:
Janet Jackson on the cover of Rolling Stone, 1993

(answers.com)
Lindsay Lohan on the cover of Elle, July 2005

(bunnyshop.com)
Christy Turlington & Bono on the cover of UK Vogue, 1992

(newfrontiers.com)
Kate Moss on UK Vogue, Sept. 2005

(condenast.co.uk)
And Kate Moss on German Vogue, July 1995... but I do not have the source for my image.
