Some of the MSDN Sharepoint Classes for WSS3.0

Microsoft.SharePoint.SPSecurity.SPOperationCode MSDN link
Microsoft.SharePoint.Administration.SPAdministrationServiceJobDefinition MSDN link
Microsoft.SharePoint.Administration.SPJobDefinitionCollection MSDN link
Microsoft.SharePoint.Administration.SPRunningJob MSDN link
Microsoft.SharePoint.Administration.SPRunningJobCollection MSDN link
Microsoft.SharePoint.Help.SPHelpMerge MSDN link
Microsoft.SharePoint.WebControls.BackLinksIterator MSDN link
Microsoft.SharePoint.WebControls.BaseXmlDataSource MSDN link
Microsoft.SharePoint.WebControls.ContentDatabaseSection MSDN link
Microsoft.SharePoint.WebControls.ContentDatabaseSectionMode MSDN link
Microsoft.SharePoint.WebControls.DataTableDataSourceView MSDN link
Microsoft.SharePoint.WebControls.DiffSelectorIterator MSDN link
Microsoft.SharePoint.WebControls.GroupPermissions MSDN link
Microsoft.SharePoint.WebControls.IDesignTimeHtmlProvider MSDN link
Microsoft.SharePoint.WebControls.IFormDelegateControlSource MSDN link
Microsoft.SharePoint.WebControls.InputFormCheckBox MSDN link
Microsoft.SharePoint.WebControls.ItemHiddenVersion MSDN link
Microsoft.SharePoint.WebControls.IXPathNavigator MSDN link
Microsoft.SharePoint.WebControls.LinkSection MSDN link
Microsoft.SharePoint.WebControls.LinksTable MSDN link
Microsoft.SharePoint.WebControls.ListViewSelector MSDN link
Microsoft.SharePoint.WebControls.MenuSeparatorTemplate MSDN link
Microsoft.SharePoint.WebControls.RadioButtonChoiceField MSDN link
Microsoft.SharePoint.WebControls.RecentChangesIterator MSDN link
Microsoft.SharePoint.WebControls.RepeatedControls MSDN link
Microsoft.SharePoint.WebControls.ServerSelector MSDN link
Microsoft.SharePoint.WebControls.SiteAdministrationSelector MSDN link
Microsoft.SharePoint.WebControls.SiteActions MSDN link
Microsoft.SharePoint.WebControls.SPSqlDataSource MSDN link
Microsoft.SharePoint.WebControls.SPXmlDataSource MSDN link
Microsoft.SharePoint.WebControls.SubMenuTemplate MSDN link
Microsoft.SharePoint.WebControls.VersionDiffIterator MSDN link
Microsoft.SharePoint.WebControls.WebApplicationSelector MSDN link
Microsoft.SharePoint.WebControls.XmlUrlDataSource MSDN link