Elegant Fostoria glassware is frequently bought and sold on eBay, and sometimes misidentified. Despite its unique acid etched patterns and distinct colors it still can be confused with other Depression era glassware such as Morgantown, Heisey and Tiffin. This misidentification of Fostoria can work in an eBay buyer's favor though, with a few tools used in searching.
The best resource to identify Fostoria patterns is a series of books authored by the mother-daughter team of Milbra Long and Emily Seate. Fostoria Tableware 1924-1943, Fostoria Tableware 1944-1986, and Fostoria Stemware are each filled with photographs and detailed information about Fostoria's numerous patterns and pieces. While the pricing data is a bit dated, it will give you an idea of how much this glassware has increased in value since its creation. A newer volume by the authors, Fostoria Value Guide, offers more contemporary pricing. Typically though, eBay prices are consistantly lower than book prices; at the time I am writing this Fostoria on eBay goes for roughly two thirds of what it is valued at in Long and Seate's books. These books will familiarize you with the patterns common to Fostoria, and in time you will be able to spot a Fostoria piece regardless of how it is labelled. If you go antiquing, this is a very handy skill.
If you are using eBay to do what I call "treasure hunting," looking for pieces that have not been identified as Fostoria, here are some tips to help you search. Using the category Pottery and Glass > Glass > Glassware define your search using the terms "etch," "etched" and "etching," and a specific color such as "green," "pink," "rose," "blue" or "azure. Because Fostoria's color lines were given pretty names like azure and rose, but sellers typically use the more common blue and pink, you'll need to search under both. So, you will do searches for "etch pink," "etched pink," and "etching pink," "etch rose," "etched rose," and so on. Don't narrow your search beyond "glassware" in order to include misidentified pieces; don't assume a seller of a "Heisey pink etched goblet" really knows it's a Heisey goblet. If they don't list a pattern name, they may well be guessing it's Heisey.
Doing such a search will lead you to etched Fostoria pieces being sold by people who have not identified them as Fostoria (and are likely to be underpricing them significantly as a result). Even if you don't want the particular pieces you find, you can help the seller by tipping them off to the real identity and value of their item. It never hurts to do a kind thing for another eBayer!