A tricyclic antidepressant is a bit extreme for anxiety disorders... no way.
Honestly with agoraphobia, you just have to push yourself into uncomfortable situations until you can't stand it anymore, then push further each time. Its a process of desensitization.
If you don't do that, you end up like me... I'm trapped in my room 24/7. I will go to doctor's appointments and that's it. I live my life in my room because its too much to handle outside crap.
Klonopin is a wonderful med for agoraphobia but its extremely addictive and it likes to poop out, leaving you stuck with an addiction and no relief.
Really... the best thing you can do is push yourself and avoid the meds. The only meds that really work are the GABAergic medications (and the GABAergic drugs like alcohol even) and they all carry a risk of dependence, tolerance, and serious withdrawal.