I suggest putting your profile on Monster, CareerBuilder, ect. Wait a while to see what companies bombard you constantly with recruiting e-mails. Those are the agencies to avoid because they are the ones with the highest turnover due to being MLM's, inferior products, ect. This is not to say there might be some good start-ups out there aggressively recruiting. Some to avoid: NAA, United American, UGA(Mega). Research before you interview. Career Fairs for strictly insurance? That's a good question.
LOL, that is what exactly happened, I almost wanted to give NAA a shot...that is why I like to go to a fair to actually talk to companies that I am interested in....
I doubt you will find a job fair specifically for insurance careers. But it is not unusual to find agencies & sometimes carriers at job fairs. If there is a college campus near you ask if they are going to have recruiters on campus anytime soon. They may let you come, especially if you are an alumnus.
Agency recruiters are usually looking for people with a business background, age 40 and up.
Carriers look for a variety of backgrounds but usually hire right out of college.