First thing you want to do is check your budget. Hotels, resorts and guest houses are available in every price range but you need to know how much you want to spend for your accommodations. Depending on the time of year, you can find a room in prices ranging from USD $10 up to a couple hundred dollars per day.
Next, figure out where in Pattaya or Jomtien you want to stay. There are three basic areas in Pattaya to consider north, south and central. The northern end of Pattaya is a little less crowded but further away from the nightlife. Central is in the middle of all the beer bar action. And, south is closest to the infamous Walking Street. Rooms in all price ranges are available in all areas. And transportation is not a problem anywhere in Pattaya.
If you want to spend time at the beach, none of the above areas are recommended. Jomtien is a bit better or go to an outer island, like Koh Larn, to get your toes wet. I would not go in the water at Pattaya Beach. Jomtien may also be a better place to stay if you are bringing over the family. It is close enough to Pattaya, but far enough away from the naughty nightlife.
Once you have decided on which...