find some friendly people to take pictures of... build up a portfolio... then advertise yourself in the yellow pages or on a website.
there may be different rules in the US, but here we just need to register a business name and do the appropriate procedures at tax time... (filling out a business tax return and claiming your income, etc.)
as for where to get pictures printed, every photographer has different preferences... just try out the labs in your area... look for quality, price and convenience (its really not convenient to drive to the other side of towm for processing)