hi i have over 800 DVDs no original cases all in leather DVD cases where can i sell?

The value is probably close to nothing without the original cases.

Without cases, it probably won't catch much attention unless it is sold as a giant package at a heavily discounted bulk rate (ie. a penny per disc or less).

You'll find out its market value by selling them as a few separate lots on eBay. Losing the cases pretty much kills collector interest for anything but the rarest DVDs. So lots like yours are for pure movie lovers looking to get a decent collection all at once.

I'd guess something like $100, maybe $150 as one lot. Could be more or less depending on how you frame the auction.