I was trying to figure out how to do a Google search on the idea of gift cards, and the only thing that comes up are a million and one (well, ten or twenty) websites that offer gift cards for sale. Even a clustered-search engine (Clusty, Kartoo) was unable to find anything other than commercial products. I figured my nearest librarian, my wife, would know a better way to search, maybe some keywords I hadn't considered.
She sent me down a completely different path: Check the local library and search their business publications catalog. Our library, just happens to have tons of stuff online that works with my library card number, including the ABI Inform database of articles from the business press. That led me down the path I needed for "stored-value cards."
Woo hoo, Marci rocks!