Use this free wizard to develop VSTO-based COM add-ins for MS Office using Delphi Prism exactly in the same way as you do it using VB.NET and C#. Benefit from all features of VSTO, including its programming and deployment models, Ribbon designer etc.
This is a free sample add-in (ready to install and use) that adds some useful features to Microsoft Excel. It contains a full source code in VB and C# and supports Excel 2003 and 2007. The add-in works in VSTO 2005 SE and VSTO 2008 (VB.NET, C#).
Easily develop professional extensions for Microsoft Office. Build Office add-ins with minimal coding and debugging, customize Office 2007 Ribbon UI and Office 2003 toolbars with special visual designers in your VSTO 2005 (SE) and VSTO 2008 projects.
An extension of Visual Studio Tools for Office 2008 and 2010 that enables you to customize Outlook views and Outlook forms with any .NET controls. It allows adding advanced regions to any VSTO project, a new or existing one, in Outlook 2010 - 2003.
Invantive Dotnet Optimizer provides a graphical user interface to NGEN. It allows you to easily optimize the start time of your Microsoft .NET applications by pre-compiling