Right now I use HEC to do some very basic modeling and I would like to expand my knowledge of the program. Can anyone recommend a course or an educational path to help me with my task?
I assume you mean HEC-RAS?
If so, the HEC Team has put together excellent training resources that you can complete on your own time. This include webcast, tutorial with material, online vidoecast, and many yoututbe videos to go along with it.
You may want to check out it at this link from HEC:
If you're in the US, you could check your local transportation department or regulatory authority to see if they offer any classes. In Virginia, for example, the VDOT Transportation Training Academy occasionally offers a two-day HEC-RAS course (for a fee). It's not enough to become an expert or anything, but something like that could give you a launching point for what you might want to learn more about.