in the item view i let display "Tags"

Now i see the tags, if i use the link everything works fine, but which php-file is responsible for the display.

I need to add some "addthis" code.

It's the tag.php file just make sure to use overrides.

More info can be found here
getk2.org/documentation/tutorials/174-templating-with-k2-and-the-concepts-of-sub-templates

and here:

www.joomlaworks.net/blog/item/194-k2-inheritance-sub-templating

Thx Krikor,

had a overwrite issue

You 're welcome :)