I give casting call notices for Illinois since I grew up there. When I first moved to L.A. in the 1980s, I worked this circuit to get a better understanding of the business of show. I came back at age 30 and worked on newspapers and radio and newspaper syndications in Illinois, and more. Always kept my hand in many pots. Now, going back to Illinois from L.A. and back again, and back again, and back again (you get the picture)...it goes on, when it can. I now do it more of a hobby as I approach my mid-50s. But, I like to update how the business works for those who are thinking the same thing I did after college. Going there was like getting a Master's Degree in the business, with on-hands work. While working as extra/stand-in and bit played in Hollywood, I also worked on newspapers (in the 1980s/early90s) and had a corner on the newspaper syndicate market for trivia and information/lists. Today, I found living in L.A. full time was not needed anymore. So, split the time, and do it on my own.
One tip: do not do it if you are not going to get paid. That adage of getting to work on a film in exchange for working for nothing is BS. That worked well in the 1970s-1980s, but no more. In L.A., sign up for as many agencies as you can. In Illinois, there are many to choose from as well. Do not listen to friends about this as they will always say you are nuts to try this. Treat it like a job and be professional and work will come your way.