My toad hasn't been eating and he's getting thin

[Drayvan]

A vet does sound like the best course of action, you say he is WC so it could be possible he has internal parasites which would lessen his appetite if they are filling his digestive tract. A vet can do a fecal sample for you to check and then treat him.

[VictorsMom]

Go to this website to find a veterinarian in your area that will treat amphibians:
www.arav.org

You can also contact the Arizona Exotic Animal Hospital and ask for a referral for a local exotic vet:
Arizona Exotic Animal Hospital