To find such a specific item you are probably wise to check online in specialty costume and Halloween stores. You can also source locally but may have to have the item custom made by a store that provides this service.
You can purchase a variety of green dog costumes from http://www.buycostumes.com/. There are many green dog costumes that you can pick for children or kids.
at partycity.com
you can find cheap costumes for kids at wal-mart. they always have an assortment of costumes that are fairly inexpensive. another store you could try is target or kmart.
Cute dog costumes do exist in the world, and they come in a variety of styles. You can find a dog costume a your local costume store, as they have started to carry dog costumes.
www.winning costumes.com
Information for princess costumes may be found: www.partycity.com �ۼ Halloween Costumes �ۼ Girls Costumes www.halloweenexpress.com �ۼ Kids Costumes www.costumecraze.com/Traditional-Costumes-Princess-Costumes.html
well there is a movie like that and its called Hotel For Dogs and that a really good movie it is great for kids!
Dog costumes for large and small dogs can be found at specialty stores such as Party City and Costumes Super Center. Good deals on dog costumes can often be found on eBay or Amazon.
M and M world at the mall!
Halloween web sites usually have cute dog costumes. the mall usually has a haloween store that sales costumes starting the end of summer. usually has alot to choose from
One great site to find patterns and directions for making Halloween costumes for kids is Family Fun. You can find them at http://familyfun.go.com/halloween/halloween-kids-costumes/. Another good resource is http://www.allcrafts.net/kidshalloweencostumes.htm. I also recommend that you check out http://sewing.lovetoknow.com/sewing-patterns/halloween-sewing-patterns for a list of places to find free patterns.
You should be able to find child costumes at a decent price at any of the following websites: www.costumeexpress.com, www.partycity.com, www.spirithalloween.com, etc.