I can get the permalink of a specific post tag or category, but what if I want to get the permalink of a custom post type? I can’t find anything in the Codex or anywhere else about how to do this.
How about href="https://wordpress.stackexchange.com/questions/32014/<?php echo get_post_type_archive_link( $post_type ); ?>", where $post_type is your post type?
Further reading: Codex