I am new to design and looking to get more familiar with different materials available to print on, different paper weights, learn about vinyls, etc. Does anyone know of some good sources to learn more about this?
Modern machines can print on pretty much anything, the best thing to do is find a local print supplier and have a look at some items they produced. Some large printers can send you actual samples of different material.
Another thing you can do is look for a trade show in your area, these are multi-day events where all these providers and equipment makers will show off their tools and techniques. There will possibly be seminars and live demos you can attend. The Inprint trade show in Munich, Germany is one good example.
One thing i did recently was order a free business card sample pack from Moo which includes different types of paper and other finishes like varnish, silver layer, gold finish, etc.
The printing methodology is something that evolves and changes quickly, any current statement in materials and printing systems may be outdated in months, specially for the digital and 3d printing systems. If you have the opportunity, the best formula to keep abreast of the most current is going to an exhibition of printing, graphics and publishing. I had the opportunity to go to a super fair in Milan, and I can assure that a whole day in one of these fairs is the equivalent of two years of a postgraduate degree in Design Technology applied to printing. Here is a website with an agenda of the main exhibitions:
This is a blog and calendar of one of the international main printing fairs: