How to find out what your Vinyl Records are worth?

Discogs is a site that has many members and a huge database of records. You can buy or sell vinyl via this site.
Popsike tracks bids on e-bay for records.

Vinyl shops in The Hague:

• Empire Records, Korte Houtstraat

I have a new (never unpacked) grammophone or turntable….with an adapter I can use it to digitize my vinyl collection… Behringer UFO202 audio interface USB is such an adapter.