The only things you need
for endurance are a sound horse, tack that fits your horse (and hopefully you), and a good brain (def yours and hopefully your horse too!).
Going to rides near you as a volunteer is always my first suggestion. There you can not only get a close-up view of what goes on, you can hopefully find some local people to you to act as mentors.
Check out AERC's website
(AERC = American Endurance Ride Conference, the governing body of the sport). They have links to the ride calendar (where you can find rides in your area), FAQs, advice for new riders, etc. Another great resource is the Old Dominion's website
, which has great links in the 'education' section (the rides themselves aren't near you unfortunately, but the info is good regardless of where you ride). Another fantastic place to go is the AERC's YouTube channel
. There are videos about camping and what to expect at vet checks, etc.
Another great resource is facebook. There are many groups for distance riding, including some "green bean" groups which are specifically meant for newbies. I am involved in mostly groups for the Northeast, and I suspect there are similar groups for your region (which is technically Central, but you may find rides in the MidWest are not too far either). The groups that deal with the whole country can be a bit.. overwhelming.. so please don't join one of those and think everyone involved in distance riding is crazy!