Where can I search by card for decks in major tournaments?
magic.tcgplayer.com allows you to search deck lists based on a particular card being used.  Here's the search for Tibalt.  You can also use their Deck search tools to limit by format and place finished in addition to specific cards.  

Limiting your search to include decks using Tibalt, in the Modern format, that placed at least 1st through 64th returns zero results, indicating that no successful deck in the entire TCGPlayer database has ever used Tibalt.