The SharePoint Web Services

Windows SharePoint Services was being designed and developed during the time when Microsoft was beginning to heavily push Web services. It should be no surprise, then, to find out that you can get at the data in SharePoint through Web services. In fact, there's not just one Web service involved; there are 16. Here's a brief rundown of the Web services that a SharePoint server makes available out of the box:

http://server:5966/_vti_adm/Admin.asmx - Administrative methods such as creating and deleting sites
http://server/_vti_bin/Alerts.asmx - Methods for working with alerts
http://server/_vti_bin/DspSts.asmx - Methods for retrieving schemas and data
http://server/_vti_bin/DWS.asmx - Methods for working with Document Workspaces
http://server/_vti_bin/Forms.asmx - Methods for working with user interface forms
http://server/_vti_bin/Imaging.asmx - Methods for working with picture libraries
http://server/_vti_bin/Lists.asmx - Methods for working with lists
http://server/_vti_bin/Meetings.asmx - Methods for working with Meeting Workspaces
http://server/_vti_bin/Permissions.asmx - Methods for working with SharePoint Services security
http://server/_vti_bin/SiteData.asmx - Methods used by Windows SharePoint Portal Server
http://server/_vti_bin/Sites.asmx - Contains a single method to retrieve site templates
http://server/_vti_bin/UserGroup.asmx - Methods for working with users and groups
http://server/_vti_bin/versions.asmx - Methods for working with file versions
http://server/_vti_bin/Views.asmx - Methods for working with views of lists
http://server/_vti_bin/WebPartPages.asmx - Methods for working with Web Parts
http://server/_vti_bin/Webs.asmx - Methods for working with sites and subsites
To use any of these Web services, replace server with the name of your SharePoint server. Because they're implemented using ASP.NET code, you can retrieve the matching WSDL file for any service by appending ?WSDL to the end of the URL. When you do so, you'll discover that each one supports multiple methods, making this one of the richest sets of Web services of any current product. For full information on the available Web methods, download the SharePoint Products and Technologies 2003 SDK.

VB.NET to SharePoint
http://www.developer.com/tech/article.php/3104621/SharePoint-and-Web-Services.htm