EDDB is popular with a useful set of search options but I prefer Thrudds http://www.elitetradingtool.co.uk
Neither are bang on accurate owing to the way the data is crowd sourced. Useful to get a target zone to investigate further and note down or snap photos on your mobile for reference.
Very useful for the 'universe' tab as you can search for system data if you know the name. Saves a lot of time flying between systems looking for local stations.