I have an acquaintance who is a collector. He would like to set up a web site devoted to his hobby and include on the site the ability for people to click on a link related to a specific collectible item and be taken to a specific vendor's site (or perhaps the visitor would be offered a very short list of sources for that specific item) to purchase that item. Is there a name for this vendor-specific online advertising?
What he needs to know is how to get this PPC system working. Is there a middleman, such as Google AdWords, that handles such vendor-specific PPC transactions? Would he have to contact each vendor individually and have them sign a contract -- or would the middleman-service do that?