Congratulations! I am 35 and back in school as well!
It was pretty easy at the community college as there were a lot of people like me at the school. I was generally the oldest person in my class, but I always had something to say and most people listened to me and respected me. It was fun and I had to laugh at myself about being nervous what to wear on the first day.
In the 4 year school I transferred to it is more awkward. It is definitely geared towards younger students. I still enjoy it and do very well with less effort than when I went at age 18. A lot of my classes are things I have already learned by the seat of my pants (so to speak) and it is being presented in an organized fashion.
A few points, I agree about the books each semester/quarter. The first thing I do is go to class before I buy ANY books. I ask the professor if the books are all neccessary and if they have an old one I can borrow. At least one professor a quarter does have one, which is a HUGE happy thing! Then I go off-campus for my books.
Also, look for the Re-Entry Center. This is for people like you, who are coming back to school after an absence of 5 or so years. It is a WONDERFUL resource, with lots of support, advocates, and help in navigating the school.
It is easier to get into crack of dawn classes than others if you are having trouble. For some reason 19 year olds don't like to take 7am classes? LOL!
Make sure your professor KNOWS you personally. Talk to them, go visit them at office hours, have a voice in assignments you turn in. This will be important for letters of recommendation for scholarships and other programs. But also, if you have a real life issue where you cannot go to class or complete a project on time, they are more likely to excuse you than if they don't know you.