You can check out the BU Bookstore (Barnes and Noble), which is on the other side of Commonwealth Avenue from Fenway. Worst case scenario, you can pick up an item of his alma mater for him to sign.
Thanks...luckily the coordinator of our conference bought signed copies of Miracle for everyone. All of the stores near the hotel only had Red Sox stuff and with it being Sunday that I had time to shop most stores were closed. All good though and he is an incredible speaker with some really great stories to tell.