These days Grim Fandango can be pretty hard to find in retail stores, and it isn't even available on the LucasArts company website anymore. However, with a little searching, it should be possible for you to get your hands on one of these.
To try and help you get a copy of the game we have listed everywhere we know where it can still be purchased along with a price estimate where available. If you know of any others, let us know so we can add it to the list.
United States of America
Amamzon.com Marketplace - $40
GoGamer.com - $30
Overstock.com - $40
Amazon.co.uk Marketplace (used)
Play.com User Trade (used)