From the old head point of view...a bama bamma? originally meant someone who is patently country -- like from Alabama. Someone who dresses country, talks country, walks country, drives a country-ass ride, someone whose picture you would see in the dictionary beside the word "bama". This person would be totally unaware of and oblivious to his or her classification as such. People could be laughing at a bama right up in his or her face and the bama wouldn't have a clue. In later years its meaning has expanded to include anyone/anything that is outside of the current level of acceptability. From the old head/old school point of view "bamma" is a misspelling of the term. It should be spelled "bama" -- as in short for Alabama.
Lookit dem raggedy-ann ass clothes he wearing. Yo dat nigga is a ice-cold bama bamma!