I think littlegiant and hostBrain got it right. You probably don't want to be looking at "starter plans", no matter how generous the bandwidth allowance may seem. These kinds of traffic spikes can shut a server DOWN if you're one of 80-100 sites on a server. I'd venture to say it's time to start shopping for VPN hosting or dedicated. An $8.95 per month plan (or similar) just isn't gonna cut it for you, and you're going to end up in the same boat, no matter who you use.
You should consider posting whatever stats you have on Web Hosting Talk and let the pros there advise you. Otherwise you'll just have to migrate again when the same thing happens.