Slipstream SharePoint 2010 SP1 and Language Packs SP1 into RTM Builds

Slipstreaming SP1

1. Download SP1 for either Foundation or Server.
   1. SharePoint Foundation SP1 - http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=26640
   2. SharePoint Server 2010 SP1 - http://www.microsoft.com/download/en/details.aspx?id=26623
2. After downloading, extract the SP by running the following command.
   1. officeserver2010sp1-kb2460045-x64-fullfile-en-us.exe /extract:C:\destinationfolder\
3. After doing this, copy the extracted files to the UPDATES folder of your SharePoint Server 2010 installation directory
4. Install SharePoint Server 2010. At the end of the process, everything in the updates folder will get processed.

 

Slipstreaming SP1 for Language Packs

1. Download SP1 for the Language Packs and choose the language you need.
   1. SharePoint Foundation 2010 Language Pack SP1 - http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=26629
   2. SharePoint Server 2010 Language Pack SP1 - http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=26621
2. After downloading, extract the LP SP by running the following command
   1. serverlanguagepack2010sp1-kb2460056-x64-fullfile-en-us.exe /extract:C:\destinationfolder\
3. After doing this, copy the extracted files to the UPDATES folder of your Language Pack installation directory, making sure you match languages
4. Install each desired language pack. At the end of the process, everything in the updates folder will get processed.
1. Language packs installation cannot be slipstreamed into the install of SharePoint itself. Separate installers must be run. 

Source: http://blogs.msdn.com/b/ronalg/archive/2011/07/11/slipstream-sharepoint-2010-sp1-and-language-packs-w-sp1-into-rtm.aspx