I know a lot about frogs and i have them in my garden pond every year.
And i dont think you can buy ordinary frogs in pet shops you can buy small frogs and all different types of frogs and they will be quite expensive.
If you are looking for an ordinary frog set up a pond in the garden and there are these plants that you put in the water and it helps the get more oxygen and there will be loads in no time .
hope i have helped a little.

Most pet shops carry frogs and turtles. My nephew loves frogs and turtles and over the years I have bought him many different kinds of turtles and frogs and almost all pet shops we went to had them.

no they do them in reptile shops or some pet shops