Go for a SEASONIC one, they are a huge OEM manufacturer for many powersupplies and make top quality products.
Something like this would be great (http://www.newegg.com/Product/Product.aspx?Item=N82E16817151121). All of the cables are black so you will not have any ugly colors showing through the sleeving or at the connectors. Also 660w is plenty or overkill for most modern computers, but it really all depends on the specs of your computer that you have not mentioned in your post.