How to add new toolbar button in IE ?

Hello,

This may be a very basic question, but your help would be greatly
appreciated. I would like to know the necessary software to install so
as to create a new toolbar button programatically for Internet
Explorer.

I would like to create a downloadable software that will create a new
toolbar button in IE, and I would like to use this toolbar to do
various activities.

Could someone help me on how to start with this ? What software do I
need and what is the best programming language to use ? Is there
anything available for free or do I need to purchase them ?

Any quick help would be greatly appreciated.

Thanks
Balaji

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