If you're into fashion sketches or illustrations, there's quite a few blogs today that post a lot of art related content. I love Garance Dore's sketches and she even sells some of her drawings as prints! My two favorites of her are black and white:
Paper Fashion creates some really beautiful water colors:
Designer Kimberley Gordon (of Wildfox) does water colors of models that I'd love to own! Do you have some favorite artists? We would love to hear!