Anyone ever had luck with the stop-leak stuff?

If I am very mechanically-inclined, could I fix such a leak myself? No idea where it’s leaking yet. Gonna go to YouTube and discussion forums later tonight to figure out common causes/sources. Car is a 2001 Malibu.

For reference, I’ve done a lot of brake work, replaced alternators, random parts, and recently replaced the radiator on. Navigator (an incredibly complex task for what it was)