Many tattoos can be excised all at once or a portion at a time. It depends on the size and if the remaining skin can be pulled together without too much pull on the stitch line. Another alternative is to have it cut out and replaced with a skin graft, but that would probably be your last option, because skin grafts for this sort of thing normally don't look like normal skin.
You can go to the website for the American Academy of Dermatology and click on the "For the public" heading. Under "Find a dermatologist" click "advanced search" and for Specialty, select Derm Surgeon. Fill in the zip code or city and state to find names of doctors to call.