Sharepoint 2003WSS 2 – reporting
Out-of-the-box reporting tools for SharePoint 2003
http://technet2.microsoft.com/windowsserver/WSS/en/library/6921bcb7-bc09-4c9a-b841-5467f2a59cda1033.mspx?mfr=true
Microsoft reporting tools for SharePoint 2003
http://www.microsoft.com/downloads/details.aspx?FamilyId=49159368-544B-4B09-8EED-4844B4E33D3D&displaylang=en
http://www.microsoft.com/technet/scriptcenter/tools/logparser/default.mspx – this might be only IIS logs but worth a look
Other third-party softwarecodeexamples
http://www.15seconds.com/issue/050623.htm
http://www.vyapin.com/products/enterprisenetworktools/arksp.htm
http://www.idevfactory.com/products/uspm/default.aspx
http://www.quest.com/site-administrator-for-sharepoint/