There are 12 cars on the back, so they're from the Desert 12 series.  You got these for rock bottom pricing.  Did you read this article about this series?

http://www.takefiveaday.com/20…..art-cards/

One way to get a feel for what an item is worth is to do a search for it on eBay, to see what people are asking for and if many people are bidding or not. Then, do an "advanced" search for the same item, but with the "completed" sales box selected; this will give you a list that shows what people really paid, or if the items went unsold (IE item was perhaps overvalued, etc). 

blanebrian said:

I just read the one page about the desert series but how rare are the 12 car series and how much do they normally go for thanx