Replace auto trany with manual trany?

So, I''ve got my 2000 Mazda Millenia, and I love the power, I was just wondering if it would be possible to put a manual transmission in?  I don''t know a WHOLE lot about cars, but I don''t see why this wouldn''t be impossible!  If so, what kind of transmission would I need to get?  One from another Mazda, I''m assuming.  Also, would this be insanely expensive?  And would I be able to get much for my auto transmission (if I wanted to sell it to, hopefully, make up some of the costs)?

Thanks so much!

I don''t believe a manual was ever used in the Millenia and that it also has a unique engine.
Yes, it would be insanely expensive and very difficult imo. Cheaper to replace the car.