How to link left column ico

[flyhead]

Could someone please let me what files I need to access for giving customer information when they click on icon on the left column. We offer rush orders. I currently have a rush order icon in the left column. I would like to give information and cost about this service when they click on it. Could someone let me know what files I need to access in order to make this modifications.

 

Here is the URL www.masterdatachecks.com

 

 

Thanks