Well OK, maybe not the most amazing banner ads you have ever seen. However with Google's new Display Ad Builder tool even artistically challenged people like myself can quickly build professional looking banner ads to be displayed in the AdWords content network.
The Display Ad builder has over 30 design templates to choose from. Some are specifically related to certain verticals such as finance or travel, and others are not themed in any particular fashion.
To get started you will need to get together a few assets. You will want to have a version of your company's logo saved with a max file size 50K in .png, .jpg, or .gif. format, with the following dimension(100×36). I would recommend a .png where the background is transparent. You will also want to know the hexi decimal values of your websites color scheme, and you will want to know the URL of destination or landing page.
The following screencast will walk you through the process of creating a banner ad with Google's new Display As Builder.