How much is worth a baldwin ellington piano from the 1970s and where can i sell it?

Craigslist is your friend here.

You need to do some research on the piano. Here is a site that may help a bit...

http://www.bluebookofpianos.com/serial1.htm

Keep in mind that book value is one thing, the local market is another. As an example, I was the owner of a very good Yamaha studio piano - a true studio instrument, not something you'd buy for a home. it was also from the 1970's. Wonderful action and sound. But I needed to let it go as I did not have room, and it was in storage. I've seen them sell on eBay in the $1500 area in minty condition and delivered. I pulled $300 for it locally.

is it a straight up or a grand ? Is it signed by Liberace ? Otherwise its simply a old piano that no one wants except for sentimental value . Try $ 400 to $ 3000 . Lets put it another way , if it had value you would have sold it 4 years ago.