We went through a similar situation with AXH. I'd given him our daily routine with times (up, breakfast, school, home, dinner, bath, bed); he started calling repeatedly during the work/school day. It was fairly easy to shut down since we were still going through the divorce and custody hearings and he couldn't really tell the judge that calling my cell phone while DS was at school meant he was calling DS. However, he then switched to calling several hours after DS's bedtime and got incredibly mean when I refused to wake DS up. I ended up having to tell him by e-mail that DS will be available for calls from x to y pm on *these* days. I don't know if it would have worked in the long run or not, because shortly after setting that, he lost all visitation rights. (It sure did/does feel nice giving myself permission to ignore any phone calls, though.) And, I don't know if it would work in your case, but your lives are separate now, and your evenings shouldn't have to be held hostage by his incessant calls.
Forourgirls and WTBH, and any one else dealing with similar stuff, I just wanted to let you know that you'll get through this and it will change, and it most likely won't last nearly as long as you fear it will. I didn't believe AXH would ever leave me alone; I thought I'd be dealing with him, if not daily, at least weekly ForEver until DS got much, much older. It lasted a few years, which I know is a long time when you're in the middle of it, but not the 12 years I was sure it would. There's hope. And you get stronger the longer you're away from him, so if, by odd chance, _he_ doesn't change, _you_ do. You get stronger and and find new tools to use to able to deal with him without getting caught in the spiral of crazy. Hang in there.