Most importantly I would suggest getting it done with needles rather than gun.
Guns can lead to so many problems and cannot be cleaned properly between piercings. Even if you think it is ok it may take years before your ears show the bad affect of gun piercings (it took 8 years for mine) So obviously stay away from places like claires accessories. Instead go to a proper tattoo place. My brother swears by tattoo zoo (has got both ears, lip, tongue, snake bites, eye brow, nipple done there). Some find raven ok but a few friends have had bad experiences.
Tattoo zoo is probably the best I could recommend. They also give great after care. I needed help for a belly button piercings done elsewhere and they didn't mind helping and really sorted out my problem.