I am working with both amq.js (ActiveMQ) and Google Maps. I load my scripts in this order
Is there a way to make sure both scripts load before I use them in my application.js?
JavaScript files should load sequentially and block so unless the scripts you are depending on are doing something unusual all you should need to do is load application.js after the other files.
Non-blocking JavaScript Downloads has some information about how scripts load (and discusses some techniques to subvert the blocking).