To find a U.S. Code section by public law number, you must conduct a full-text search.
From the U.S. Code database, click on Advanced Search at the top of the main page.
Example: “Pub. L. 107-42”
You can also search using the One-Box search bar at the top of the main page. For this type of searching, you would enter “Pub. L. 107-42” AND volrefdate:2000 AND title_num:49 and then select the Just search for option.