jointhefediverse.net seems to be a commonly linked resource for directing people to join the Fediverse.
Curiously, it does not list Lemmy under the list of Reddit alternatives. Their GitHub README explains why.
Previous relevant discussion: https://lemmy.ml/post/78808
But by buying a tesla youre giving elon money and promoting his product which is much more closely tied to his views than lemmy is to the devs views.