SharePoint SDKs Updated to cover SP1

Version 1.3 of the WSS v3 SDK can be downloaded here:

http://www.microsoft.com/downloads/details.aspx?familyid=05E0DD12-8394-402B-8936-A07FE8AFAFFD&displaylang=en

And the MOSS SDK can be downloaded here (covers and includes WSS v3, you don't need both):

http://www.microsoft.com/downloads/details.aspx?FamilyId=6D94E307-67D9-41AC-B2D6-0074D6286FA9&displaylang=en

Note: You'll need to uninstall the old version of the SDK before installing the new one.