This is a great question, and I’m sure one than many comic book readers have thought about.  The good new is, if you want to make a comic, you can.  Write your story and find an artist draw it.  The world is full of artists, and I can say from personal experience that collaborating with an illustrator on a script you’ve written can be a really rewarding experience, and bring new dimensions to the finished product.  Printing comics is relatively inexpensive.  You can print larger runs (500 copies or more) with an offset printer, or use a print on-demand-service to print fewer copies (usually at a higher cost per issue).  And then, of course, there’s digital distribution.  You can submit your comic digitally to comiXology Submit, Kindle and Createspace (who also do print-on-demand).  Then, all you gotta do is get the word out.  Go to or table at comics shows whenever you can, there are tons of indie festivals nowadays.  Tumblr is also a great way to connect with comics readers and creators as well.  As you create, you’ll find your voice, and as you promote, you’ll find your peers and audience.  If your ultimate goal is to pitch your ideas to a major publisher, having a finished comic and building an indie audience is a great way to get yourself noticed, but you also might find, along the way, that you like doing it yourself.  The possibilities are limitless!