If you create a new hook, you have to insert it to template file.
What @joseantgv was saying is i guess: Open up product-list.tpl file, look for hooks there. For example displayProductListFunctionalButtons.
If none of these hooks are in the position you are after, you have to insert your hook ( libreecoute ) where you need to display custom information.
You can also see how you can pass product as parameter