{| |- | Price listings for stamps are referred to as Catalogs. Many countries have listings of their stamps in various versions. Your local library will typically have one or more of these, Scott's being the most common in the US. It will give you descriptions and pictures of the stamps, as well as directions on how to identify and grade them. |}
You can find 1978 Commemorative stamps of America on about.usps.com/who-we-are/postal-history/stamps-postcards.htm
You can find books on Historic stamps of America 1978 Postal commemorative society on en.allexperts.com/q/Stamps-Philately-1610/2009/2/books-stamps-great-grandfather.htm
It may be purchased online from StampsForSale which has many commemorative stamps. You may also shop at RoyalMail which has a variety of gifts and stamps.
The best place to go is just the USPS website. They're the ones that issue all the commemorative stamps and things like that. I'd start there.
H. D. S. Haverbeck has written: 'The commemorative stamps of the British Commonwealth' -- subject- s -: Commemorative postage stamps
The ones purchased from the US Postal Service include the stamps.
Commemorative Medal for Foreign Operation or Mission was created on 1993-04-13.
Commemorative stamps are typically not sold in stamp machines, as these machines usually dispense only definitive stamps, which are intended for regular postal use. Commemorative stamps are often released in limited editions and are usually available at post offices or through specialized retailers. However, some postal services may occasionally offer commemorative stamps in limited quantities at specific machines during special events.
you can buy coupons at the post office that are redeemable in foreign countries for stamps
Stamps are divided into two primary categories. Definitive and commemorative. The commemorative issues are the issues usually in smaller sets that commemorate something of someone for example trains people historical things. The definitive sets are items at are much larger sets and are used for postage and have many more values. Note that both can be used for postage. __ If you want to see all the commemorative stamps, you need to consult a catalogue because there are thousands of stamps, far to many to list here. Collections Canada maintains a website that shows all Canadian stamps issued. If you don't have access to an up to date catalogue, you could go there.
Stamps typicall see an increase in value after the 1st year on the market. This does vary depending on the stamp.
Certainly, that is what they were created for, to serve as postage. Just make sure the total face value of the stamps equals the appropriate rate for the envelope or package.