I'd like to have his skills evaluated professionally, but have no idea where I can find those services. Can you suggest where I might obtain such an evaluation?
You can call the American Psychological Association's chapter in your area, or their central office, to find the names of such professionals. I would also recommend networking with your pediatrician, as well as the psychology and social work departments of local children's hospitals. Again, your goal should not be just to have your son tested on his first-grade readiness; it should be to evaluate his overall intellectual, emotional, social, and physical development as predictors of which grade environment would be appropriate for him next year.