Where can I get a less expensive nice camera?

I love photography, I have taken so many classes as my school and I am really trying to make something out of it. The problem is , cameras are so expensive. And I am not just talking about a small digital camera that you get from Wal-mart, but a nice Nikon or Canon digital camera specifically for photography. They usually are no less than $500 dollars, and I just can’t afford that on my own.
So does anyone know of anywhere, any websites, and stores, where I could possibly pick one up for cheaper?