Please check these topics first.
What type of payment methods do you accept? like VISA, MasterCard, American Express, Discover Card or PayPal
Download bulk with respect to GIF,HTML5,Static banners.Can we download all formats at one go...
Will you customize the banners if i purchase from the list? Customization like changing content , adding our logo etc..
You can select your banner ads and make the payment , the files will be available for download and the unzip password will be sent to your mail.