- Wikipedia - There are some good introductory articles on Wikipedia, including these on instructional design, instructional/educational technology, ADDIE Model, and first principles of instruction.
- Blogs - I am constantly blogging on instructional design and related topics, and there a lot of other great blogs out there, including Dave Merrill's blog on First Principles and George Joeckel's Design Blog.
- YouTube - There are some good videos out there that introduce instructional design. Here is one I created that describes what an instructional designer does.
- Online Groups - there are a lot of different LinkedIn groups dedicated to instructional design. If you look at my LinkedIn profile, you can see those I am a member of.
- Associations - There are some great associations out there, and joining them is a great way to learn more about instructional design. I am a member of the International Society of Performance Improvement, the Association for Educational Communications and Technology, and the Association for Talent Development. I gain a lot of knowledge through attending their meetings and reading their publications.
- Articles - there are literally tens of thousands of articles on instructional design. I've written several on the practical use of design principles, which you can find here. There are also tons available in library search services and on scholar.google.com.
- Books - I would look at some of the great books out there. A good starter is The Systematic Design of Instruction by Dick Carey and Carey. You can also see my list of books I read to find other design books. Eventually, I hope to write my own introduction to instructional design book. .
- Get the Degree - If you are really excited about the field, you should earn a degree or a certificate in the field. We have both of these where I work at Franklin University.
I hope this is a helpful list of ways to learn about instructional design!