Check Walmart for DSLRs, they have a Nikon package that sells for around $500 .. that is very cheap for a DSLR, you might look at the low end Cannon camera packages too they are generally less expensive than Nikon, or Pentax. If $500 is out of your price range, you can check pawn shops, sometimes you can get DSLRs cheaper there or camera stores that sell used goods, but generally they sell high end stuff that is used and marked down.
If you want to learn photography using 35mm film, any older model camera with an adjustable rangefinder and light setting will do. Older models are generally cheaper under a hundred and are good cameras to learn with. I had an old Argus that I used when I was exploring photography.