Create Google Display Ad Set

We would like someone to design several display ads to be used in a Google ad campaign. We will supply some PhotoShop/Illustrator files that contain our logos, some images, buttons, and other items that can be used in the ad (but are not 100% necessary). We would like ads designed at the following sizes: 120x600 160x600 200x200 250x250 300x250 336x280 The resulting files should be PhotoShop files with as many items left in layers as possible, so we can modify if necessary. The ad text should be left editable as well so we can make final changes before we generate the PNG output. Ads should be visually appealing, tasteful, and semi-conservative in style.