Where do the legendary dogs go on Pokemon Silver Version?

They're all running around Johto. If you've seen one, check your pokedex to track it. If not, finding one is all luck. They frequently visit the grass west of Mahogany and the grass east from National Park and south from Ecruteak but, they appear in many places!

Hope that helps!!! By the way, they are the legendary cats, not dogs. The Pokemon Company revealed that Raikou is a tiger, Entei is a lion, and Suicune is a cheetah