Figuring out what a component does.

Have access to a lot of junk circuits.
They seem to have lots of intresting chips and transistors on them.

If a IC has 3 legs and a number on it is there anywhere I can go enter the number and I can get a datasheet on what it does or its capabilites.
Or for the other components.

In particular looking for datasheet for a NEC 2P4M IC

Type "NEC 2P4M" into your browser's search box - tons of info. Sure to be anything you wanted to know. BTW, you have a thyristor there.

NTE.com has a great search engine, try ICmaster.com also.