New template Extension

[Green]

I want to create a new extension which should display a new block in the product page.How to do this? How to change the layout of the product page without disturbing it.

[abantecart]

Try extension dev tool:

http://www.abantecart.com/ecommerce-documentation/developers

You can build layout as you need on your install and export it and include with your installation script of your extension.