Is there a report library in WSS v3? I installed the Reporting services add in to my sharepoint WSS v3 but no report library
Report Library is a MOSS feature only.
The Report Viewer 2.0 web part (and Report Explorer web part) gives you the ability to view reports on your SSRS server. The Reporting Services add-in I mentioned above only works when you are running SSRS in SharePoint integrated mode - it includes a Report Viewer 3.0 web part that pulls reports out of a SharePoint library.
The Report Viewer 2.0 web part doesn't use SharePoint libraries - it acts as a view into the reports hosted on your SSRS server (and Report Explorer lets you view a listing of available reports).
See this documentation for more details. Although it is for SQL 2008, it still applies to 2000 and 2005 versions as well, though the path to RSWebParts.cab changes depending on your version.
Sorry for the confusion.