I developed a EPOS system for my shop.
The system has a linux server running mysql and nginx. I use an Android tablet as the user interface with a barcode scanner attached.
I faced a similar problem finding a source of barcode data, I was surprised to find that wholesalers, manufacturers etc do not publish barcodes in a useful way.
I then found the Google Shopping API which allowed me to get data from Google in the form of a json structure, great I could now scan a new product and get its description and a list of suppliers prices. I have had the system working and in use in the shop since Feb 2013.
Unfortunately a few weeks ago Google closed access to the API, so I am now back to having to manually enter new products into the database.
You can still do something like
and then cut and paste.
There is a site called ean-search.com, however the data held is somewhat limited, and again no API.
There is also an outfit https://www.semantics3.com
who do have a system that has an API, Varun Sivamani is the man. I looked at using their database, but at the time (21/9/2013) they only had US data. He hoped to have EU data available by beginning Oct, I have had no time to look at it.