In order for you to be willing to build your own, you probably want some assurance that it will/can work.
I teacher engineering in high school and this is a project I do with my classes. If a ninth grader can build a working boomerang so can you. Still don't believe me, take a look at the video proof. (Note the plans are for a righty, the student in the video is a lefty he reversed the plans so it would work for a lefty.)