I have just encountered a very nice tool that helps connect TFS 2010 to SharePoint Server that was not installed with the TFS.

When Do I Use It? (From Download Site)

You can use this tool to configure an existing installation of Microsoft Office SharePoint Server 2007 or Microsoft SharePoint Server 2010 for use with Microsoft Visual Studio Team Foundation Server 2010. The tool automates the configuration of the following features with certain default values, which are explained in the configuration instructions that are included with the tool. The tool will skip configuring a feature if it is already enabled and configured.

The configuration tool is designed to configure relatively simple deployments of Office SharePoint Server 2007 or SharePoint Server 2010. The tool uses default settings to configure the features. You should not use this tool if any of the following is true:

• your deployment  requires the use of specific ports or protocols
• your deployment utilizes multiple application-tier servers for the server farm
• you want to configure your deployment with settings other than the default ones used by the tool

You can download the tool from: here

Have Fun!!!