Wow, March 25? That is not the latest KiCad... or maybe it is, for Mac...
Couldn't tell you why the button isn't there, but yeah, you can just use the selection under the Tools menu. I think you'll find you don't use it much once you learn most of the names of the parts - just press A, type a name and press enter.
And yes, figure out where the default project template is installed and add the libraries to it. I'm a bit shocked they're not installed by default. Haven't used KiCad for Mac, though.