I will be treating this as documentation of my process, rather than a "how-to" for people to copy my project. My hope is that you will either find this to be interesting or inspiring for your own projects, which may or may not be similar at all.
Since the project is very similar to other instructables, I may be more brief in certain areas, and give more attention to parts that I feel are unique to my experience.
For more information on details, you may refer to:
cerupcat's How to make a Cheap Multitouch Pad
mechatronic's Arduino Controlled Bell Tower/Carillon
Step 1: Begin with a trash can
I had to restrict myself from building a custom housing for the instrument, since I am limited in tools and woodworking skills. I decided that a trash can is tall enough and has a large enough opening that it would function well as a webcam driven multitouch surface. The more rectangular the trash can, the easier it is to find an appropriately shaped piece of glass without having anything custom cut.
I also procured a Logitech Quickcam Chat webcam. Notice from the picture that I have removed part of the base in order to leave the flattest, most stable mounting surface. I have also taped a small piece of paper over a LED on the top of the webcam to prevent any extraneous light within the instrument.