Online achives

Waybackmachine, which stores 150 billion internet pages going back to 1996.

Who is database and IP Track Down database

In some cases, you get a domain name, and want to know who owns it.
You can do this by perform a who is database search.
Here is a fairly complete list for famous who is databases:
CyberJedizen


In other cases, you may find that your computer is sending packets to strange IP address. You can find out where the IP address is located by perform a location lookup on the IP address. My favorites are IP2Location and GeoBytes IP Locator.

Here is the database for business: Corporation and Business Entity Database of New York State.