Is there some equivalent to PHP mysql_insert_id to fetch the last inserted UUID() primary key? (I always get 0. It works for auto_inc integers though)
No, last_insert_id() only retrieves that last generated auto_increment fields. You'll have to do a select uuid() first, then do an insert using that uuid.
However, note that uuids can't be guaranteed to be unique - they're simply very unlikely to collide. If you do require uniqueness, then go with an auto_increment - they'll never be re-used within any single table.