OT: Cleaning... (not sure if it is off topic though)

Anywho, I have been doing some cleaning of my car and I have been using a combo of things. Spray Nine, leather cleaner, yada yada. the problem is that all the dirt isn't coming off the gosh darn seats. My dad even brought me some industrial cleaner from work to clean them with and that didn't work. (we works with heavy machinery all day and that is what they clean the machines with). So, my question is.... Can someone recommend something that actually works? I picked up some mothers gold polish for the rims, and have a buffer that my uncle lent me to speed up that process. I was also wondering what is good for getting grease off the car, I have a few finger/handprints on the body from tinkering on the engine and such. Careless I know but we just wanted to get it done. The more suggestions the merrier. Oh I think I should mention that I live in Canada (Newfoundland to be more exact) so some things that is readily available to you guys in the states may not be available to me. Suggest away! Thanks in advance.