My mail was hacked and I lost all my contacts. How do I recover my over 4000 contacts lost?

Last week thursady specifically, Some called me to say that I sent them desperate mail. I knew I didn't send any email. It was discovered that my mail box was hacked and the fraudster was using it to send messages to my friends in my contacts soliciting for money. I tried to change my password, I discovered that I couldn't even have access to my email again because the fraudster changed the password in the course of his operation. It took 72 hours before I could access the mail box to change the password, but when I gained access to the mail box, I couldn't see my contacts again- over 4000 contacts. How do recover those contacts?