I could help you with access and vba but haven't tried doing advertising...however I do things I don't know all the time.
If it were me I would break this down into parts. the front end vba driven database will be a number of steps, but the advertising i would imagine is hosted and distributed already. the question is how?
I would think they have an asp script or some such thing demand loading. question is how to convert to vba?
If you are making the ads your self then you have a distribution system to build, if so at least you'll know how it works. If not the builder of your system will have standard ways to retrieve data, then you have to load it with vba.
I suspect the major problem for you is distributors are driven by browser delivery and there aren't many aiming at access as a platform.
So....More info about project?