Where to find total price of cart ?

Hello

If some special products are in the cart then the shipping fee should calculated later.
When the customer checks out the absolut total must be then
"total with shipping fee extra: $ 44.00" for example
but otherwise "total: $ 44.00".

in catalog/language/english/total/total.php
$_['text_total'] = 'total';
I add an extra value
$_['text_total2'] = 'total with shipping fee extra';

But I cant find where "text_total" value is used to change in text_total2 if condition matches.

Thanks for help
Peter

Thank you! There is nothing like a good recursive text-find-in-all-files tool. ;-)

Now I know where and how to change code but how to make an extension with this information ?