There are a number of good places to look for papers and technical reports for information on operating systems. First, there are several journals that frequently publish OS papers. ACM Transactions on Computer Systems is devoted to the subject. IEEE Transactions on Computers publishes many such papers. Usenix's Computing Systems also publishes OS papers. The ACM SIG group on operating systems (SIGOPS) published Operating Systems Review, which is not refereed, but contains interesting (generally short) articles on new work in the field.
The primary conference in the operating systems field is the Symposium on Operating Systems Principles (SOSP), which is held bi-annually. Its proceedings are always published in a special issue of Operating Systems Reviews. In years SOSP isn't held, the Operating System Design and Implementation conference (OSDI) is held by Usenix. This conference was previously held annually, and titled Symposium on Experiences With Distributed and Multi-processor Systems (SEDMS). In addition, Usenix holds one or two general conferences (called Usenix conferences) each year. These conferences typically cover Unix-specific operating system and user-level topics. Usenix also has several smaller, special-purpose workshops every year. They include workshops on security, system administration, and microkernels. The conference on Architectural Support for Programming Languages and Operating Systems (ASPLOS) publishes papers on the intersection between architecture and systems - this is a good place to find papers on new uses of translation lookaside buffers, for example. There are also special purpose workshops offered by various groups. In years past, the Workshop on Workstation Operating Systems published interesting position papers on new, early research. It has changed into Mobicomm, which specializes in research on mobile computing in a similar early stage.
I presume all of you can work Netscape well enough to get to the standard search engines. One URL that is particularly useful that is less well known leads to the NCSTRL system. NCSTRL is an experimental system meant to make all the technical reports from several of the nation's top Computer Science departments available to researchers.
The most important newsgroup to watch in operating systems research is comp.os.research. There are many groups on particular operating systems that may be useful if you are investigating that particular system.