Where can i download sponge api?

i can’t find any downloads for this bukkit substitute

There’s links in various places but in case you’ve missed every link, here’s another one to the maven repo.
http://repo.spongepowered.org/maven/
The API is at http://repo.spongepowered.org/maven/org/spongepowered/spongeapi/

I recommend you use Gradle for downloading the API though.