Microsoft has created a dedicated virtual machine to study the ALM of TFS 2012 and Visual Studio 2012.
The reference article is downloadable from Visual Studio 2012 Application Lifecycle Management Virtual Machine and Hands-on-Labs / Demo Scripts.
In the article How to point to a custom 404 error Web page in SharePoint it is described how to to handle custom http 404 (file not found) error messages, with support to multilanguage.
This is for file not found errors only.
If you need to handle any http error, you can read the page Using web.config - Returning custom http error messages on IIS 7.5.
In addition to my previous blog post about the first available training material on SharePoint 2010, called SharePoint 2013 preview: first training material, Microsoft is releasing more training content.
From the Microsoft website, there is a Downloadable eBook: Explore SharePoint 2013 containing all the articles about the changes in SharePoint 2013.
In addition, there is the article SharePoint 2013 training for IT pros that contains training videos about SharePoint 2013.