Is a red eared slider turtle good for a 34-50 gallon pond?

I want to make a pond in my yard. I am a first time pond maker.Any ideas of a preformed-pond liner out of ground and what else should i put in the pond with the turtles? Where can i get red eared slider turtles with free shipping? Should i get a bullfrog instead of turtles for a first time pond owner?