Here are some very detailed databases/maps/data for objects in the sky. You will need RA/DEC (sky coordinates) or object "name" such as Messier, NGC, or IC number to begin your search.

The SIMBAD (Set of Identifications, Measurements, and Bibliography for Astronomical Data) site provides detailed info about many objects.

The Astronomical Data Center is a huge resource of charts with links to several other sites.

The Astronomical Data Service provides abstracts and links to many other sites.

The Astrophysics Data Facility provides data from several satellites plus links to educational resources.

The Extra-Galactic Database provides additional charts plus data from a variety of satellites.

The Multi-Wavelength Sky Database provides another powerful sky resource.