What can I do if my attorney will not return my calls? 

At this point, you may need to get less friendly--whether it's because of a personal or medical problem or business reversal, which at least would be somewhat excusable, or simple professional negligence, which would not be, your attorney is not responding to you, and in so doing, may be putting your intellectual property or economic interests at risk. First send him a lettter, by some method or methods by which you can prove delivery, restating what the attorney has told you--that he has information from the patent office for you--requesting it, and stating that  if you don't hear from him within 5 or 10 business days, you may be forced to take action. If he doesn't get back to you, you should contact the office of your state court system which oversees attorneys and report his lapse to them.

You might also try contacting the PTO directly and explaining that your attorney is no longer responding to you--can they send you the information directly?