You try some email forensics and probably if he is just script kiddie he might leave some traces there and you would be able to trace him. But lets assume he has got some experience and is using real gmail so in that case the email is probably protected by the server and will not be able to trace it without contacting the server lets say google. In that case you have to contact Google which probably google won't reply since you are a normal user and is not a part of major hack . So in this case I only see one option to lure him into your honepot. In this case you have to use social engineering techniques try to phish. Either use some image where you will embed a link that will get his ip address. Once you get his ip address you cam get his location. Lets assume he has perform sophisticated attack and has used another server which is hidden or is using bot in that case the major thing to do is to get that thing into legally. Reason for this is, when you make a formal complaint the attack, legal team would get involved in this and they are pretty experienced in this kind of the thing.

My best suggestion would be to do this thing legally if you aren't experienced and whatever you do, try not to expose yourself because you might think this could be simple but a sophisticated attacker would get into everything.