Here's a site I find myself referring to often in my gardening that may help answer some of your questions. It's a fairly concise compendium of garden pests, how to identify, what to do to eradicate and how to prevent. It's a great reference for beginner gardeners and experienced gardeners alike.
http://bigbughunt.com/bug-guides/us-and-canada/bug-index.aspx
The company is actually collecting data for a future app that could, potentially, warn of future outbreaks, based on the reports they've received and environmental conditions in that region. It's kind of a neat idea. It's a huge undertaking and I hope they actually get the app up and running.