Try your local library, mine has sheet music there, but most of it is piano and i had to transpose it
I am guessing, at a music store
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The internet
From the interwebs
You cant
At video game sheet music world.com
Internet
Nowhere.
I would think local churches would allow you to copy their sheet music if you asked. The related link is sheet music for the song.
you can find no hands in trumpet sheet music in the GREAT WALL OF TABLAC - MATNOG, SORSOGON, PHILIPPINES!
Find the nearest search engine and search the words... "Family Guy sheet music for the trumpet"
Legally, nowhere. It's protected by copyright law.