To see all contacts that have a particular tag, start by navigating to the Contacts menu, then click on the Contact List tab. From here:
- Click the Filters button;
- Click the Select New Filter dropdown, and choose Tags.
- Keep the status as include, then click on the tag dropdown to see all available options.
- Choose the tag you would like to investigate, and click Apply Filters.
You will then be given a list of all contacts in your account that have this tag.
From here (after selecting any/all of them using the check boxes), you can also choose to address these contacts in bulk, by adding or removing tags, unsubscribing or deleting them, or downloading a list.