I have installed and restarted my server however the plugin won't load.

I'm on 1.8.9 Java 8. Please help!

Which version of the plugin are you using? Try v2.2.2: https://dev.bukkit.org/projects/shopkeepers/files/2615597
Check your server log. It might print a message explaining why it couldn't start.
If it prints something along the lines of 'outdated/incompatible server version', then you will have to be more specific on which server version you are running exactly. Make sure you are running the latest 1.8.9 build.

Awesome! Thanks so much, it works now.

<3