@butch24350 I recently faced that myself, having just been diagnosed with osteoporosis from a DEXA scan. I generally go to Mass General for most of my specialists (I live in southern NH). I went through their list of endocrinologists and rheumatologists (they also treat osteoporosis and my PCP actually told me to go to a rheumatologist) and checked to see which ones mentioned osteoporosis. I already had an endocrinologist for diabetes and hypothyroidism who I coincidentally had an appointment with last week and discovered that he too treats osteoporosis. I expect he is very good, he said he spends an hour for the first osteoporosis appointment because there is much to go over, but since I am post-transplant he thought too that I might be better off at Mass General.
If you are not near a large medical facility with lists of doctors that you can review, you may just need to call the doctors in those two specialties who are in your area and ask if they treat osteoporosis, or find their website and see what it says.
Sometimes asking other people who have they used can be the best way to find good doctors too but that is not always reliable. Some people may like certain doctors or find them good while others do not.
There are also rating sites like Vitals and Healthgrades where you can check ratings. I find those are not very reliable unless the doctor has a large number of ratings. If the doctor only has one or two it's too subjective.
I presume if your doctor suggested that you see an endocrinologist you probably have osteopenia at least. Your doctor is on top of things to suggest you see an endo. My PCP was not which may be why my osteopenia advanced to osteoporosis -- I never had a repeat DEXA scan and six years went by.
JK