Back in the old days,.... damn I can say that and I was really there, the first days of the Internet.... if you wanted to know something there where a lot less places to go. Most valuable place of information was Usenet (If you do not know what it is, try groups.google.com and it will give you a hint).
However there where also a lot of other places where you could refer to. Most people back in those days referred to the big corporations laboratories and this had a tremendous influence on the community.
When the cost of hosting a website became cheaper by the day people started to create there own sources of information and thereby the leading role of the computer laboratories of large companies and universities started to decline.
But they are still out there and they are still offering vast amounts of information to the public. Just to make sure that they will not be forgotten and to introduce some new sources of high quality information I like to mention some of them. If you feel I have missed just that single important website do not hesitate to send me a mail and I will create a post about it.
A good number of papers created by employees of Google can be found on a sub-page of Google labs. IBM is running some nice websites about there research and for developers. Sun Microsystems Laboratories is providing some nice work and on the developers site you can find a good deal of information. Microsoft is running there MSDN network where you can find a lot of information about how to use MS products and/or code for the MS platform. Cisco Systems is providing some very good papers on network topology which is actually a must read. On we can for sure not forget is AT&T laboratories and Bell Laboratories nowadays owned by Lucent Technologies.
I am sure I have not mentioned some very important sources but just send me a mail and I will do a follow-up on this subject.