Your first step with finding financial aid should be filling out the fafsa. You can find it at
www.fafsa.ed.gov/ If you have a tax return from 2010 then you will need that. The information you provide will determine any loans you would be eligible for, as well as work-study, grants, etc.
What colleges are you looking at? If they are saying that you need loans to go to school and are constantly calling you, I would be leery of those. If you were to take out loans, you would qualify for federal loans, and schools do not profit off of those as far as I know, so there would be no reason for them to push them that hard.
As far as looking for scholarships, there are millions of scholarships out there and so many of them go unclaimed, or have very few people who enter. I have no doubt that you could find tons of money to go to school just by spending some time looking for scholarships. Try scholarships.com for a good start.
I really do think it would be great if you could go away to school- for so many reasons. If you started planning now, you could go to school in August which would give you 5 months to plan,save,etc, and you would start with all the other freshman. It would open up a completely different world for you, which it sounds like you really need. You sound like a seriously hard working person, who's mom and sister seem to rely on to take care of things. Just think of all that you could accomplish if you could put your hard work towards school!
Also, I'm only 26, so I'm giving you these opinions from someone who has went through the whole college/leaving home thing fairly recently. It's scary to do, but it can be the best thing you ever do. Spend a little time thinking of what you absolutely love doing, what makes you happiest, and find a way to turn that into a career!