It goes back to Day 1 of your install; you can query the table directly (it's [EventOccurences]) if you need to do some complex searching.

Good idea. We should be able to add this feature in ProGet's next release.

Yes, but not easily. Automatic build records (schedule, SCM-triggered, or URL-triggered) are not "soft deleted", so you must go to the audit logs and search for the "BSHDEL" event. This can be done from the UI or directly from the database with SELECT * FROM EventOccurences WHERE Event_Code='BSHDEL'