A "free" file is not necessarily a file you are free to use, and the difference gets expensive as soon as you sell the finished object. This page gathers, on one side, the files hosted here with their written licence and matching tested settings, and on the other, external sources whose terms have been checked.
Three questions to ask about any file found online: does the licence allow commercial use, does it allow modification, and does it require crediting the author? A CC0 or public-domain licence allows everything; a "personal use" licence forbids selling the object, even a modified one.
One point is almost always misread: a so-called commercial licence usually covers selling the object you make, not reselling the file itself. Reselling or resharing the file, alone or in a bundle, stays forbidden in nearly every case, including for the files given away here.
Every file hosted on LaserSettings comes with the settings it was engraved or cut with: machine, source, material, thickness, power, speed and number of passes. That file-plus-setting pairing is what saves time; a file on its own leaves you to rediscover the values by trial.