These are very large and wide ranging data base providers which have online services, but you must register and pay for their use (except as sometimes happens, they offer a week or so free trial). Alternatively some offer their data collections on CD - ROM.
Amongst the better known geoscience databases are GeoRef and GEOBASE which you will find in for instance in Dialog here below. To use the services, find a link to databases and then look for the particular database you want to try (e.g. GeoRef)
Dialog by Knight-Ridder
OCLC Online Computer Library Center, Inc.