Although I am not opposed to a shelter dog I was looking more for breed info that would fit with us, however there is no shelter where I live. I was shut down almost a year ago after the county cut their funding.
We volunteer with a rescue organization (Catahoula Rescue Illinois) and we have fostered five dogs and transported many more. Getting a dog via a rescue organization is a great choice because you can find out about the individual dog's behavioral details. Many rescue organization dogs stay with foster families for several weeks and this permits close observation of compatibility, energy level and temperament.
You can search for rescue dogs using a number of criteria on petfinder.com Many rescue organizations also maintain Facebook pages.
It sounds like a Catahoula would not be the right choice for you, but there are rescue groups for all kinds of breeds and mixes. Our most recent foster was a Catahoula/bassett mix and she was really sweet and mellow, but with a penetrating baying bark that would be sure to scare unwelcomes away.
Remember that no matter the energy level any kind of dog should get some time outside along with social and mental stimulation every day.