Because tooltips are not stored as macros, it is not possible to track them from the Macro Usage screen or using CQL. The following SQL query should work on any database engine and will return a list of pages likely containing tooltips:
SQL
select c.contentid, c.contenttype, s.spacename, s.spacekey, c.title
from BODYCONTENT bc
join content c on bc.contentid = c.contentid
join spaces s ON c.spaceid = s.spaceid
where body like '%tooltip=%'
and c.prevver is null
and c.content_status = 'current'
order by s.spacekey, c.title;