The best place to start is with FReeper Varmint Al's website.
I like either an AR in .223 or a bolt gun in .243 for longer work. Remember - fur don't count!" If you have a helicopter you might try a 12 gauge.
I have compiled a list of coyote attacks on children. It is by no means complete, but what I have been able to find on the internet and with the help of people emailing me accounts.
Good Hunting... from Varmint Al