You can use either EnvDTE.CommandBars.Add to add temporary commandbars or
EnvDTE.Commands.AddCommandBar to add permanent command bars. This page of
mine has a lot of resources with samples, etc:
http://www.mztools.com/resources_addin_developers.htm

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Carlos J. Quintero
MZ-Tools 4.0: Productivity add-ins for Visual Studio .NET
You can code, design and document much faster.
http://www.mztools.com
> Hi,
>
> Does anybody knows how to create a toolbar with button for an Add-in
> within Visual Studio .NET.
>
> Thanks.