Microsoft will ship Update Rollup 1 (UR1) for Windows 2000--you know, that "thing" that replaces Win2K Service Pack 5 (SP5)--on June 1. Get that here: http://www.microsoft.com/technet/security/advisory/891861.mspx
On June 6, the company will release Windows Server Update Services (WSUS, formerly Software Update Services--SUS--2.0) to the Web (a type of shipment Microsoft calls Release To Web--RTW) - do a search on the right for WSUS and you'll find a blog entry with this download link!
Source: http://bink.nu/Article4112.bink
Download: http://www.microsoft.com/downloads/details.aspx?FamilyID=c0a2ca36-1179-431c-80e6-60a494d3823d&displaylang=en