Karin, can you go talk with your boss and explain that you are not being given the tools to support him as much as you want to? Sometimes that can clear the air. Also, just let him know that you sympathize with his stress, and you need him to exert some of his influence that will help you improve his workflow (ie, phones, computers, etc).
Stress is infectious and contagious. Please don't let your boss pass that nasty bug along to you.
One of the best bosses I ever had was a maniac multi-tasking micro-manager. My first week of reporting to him, I sat down in his office, smiled, and said, "I am worried that you aren't getting the support from me that we both want to achieve. The reason is that I am so new to this place that I have no influence over other people to get what you need, and I need your backing. Could you please help me to help you?"
It worked.
You are in my prayers, sweetie.