A good overview document is The Guide to Network Resource Tools which is a hypertext version of RFC 1580 / FYI 23. A Beginner's Guide to Cyberspace is a helpful introduction to the Web and other info sources on the net.
A number of places try and track new things on the Web using various
techniques. The grandfather of all is NCSA's
What's
New page which collects announcements they are sent by E-mail. They keep
them back forever, filed a month at a time. Near the end of the month, the
"current" file can get pretty long, so someone has an automatic setup to
excerpt the most recent stuff.
The newsgroup comp.infosystems.announce
carries announcements as well, and there's a collection of
past
messages catalogued and indexed. The InterNIC's
Scout Report is provided
as part of their task of scouring the net for info.
Looking into Brandon Plewe's Best
of the Web contest is also a good place to find useful sites.