I want to be able to create my very own custom voice commands and responses for my Google Home device. Is there anyway to do this?
For an end user, using IFTTT or another connector service as described in mico's answer is probably the best way.
If you want to develop an action on the Google Assistant platform, you can use Actions on Google, a toolkit with everything you need to develop a new action that other users can interact with. Note that, unlike Alexa, Google Assistant actions don't need to be installed.
To develop a Google Assistant skill, you can either:
To create voice commands for google home follow the below given steps:
Go to IFTTT.com.
Sign in or up
Click Search. Search for "Google Assistant."
Click Google Assistant Google Assistant and then Connect.
Choose a Google Account and grant IFTTT access to it. Make sure to choose the account you used to set up Google Home or the Google Assistant on your phone. (Learn how to find the account you used to set up Google Home. If you’re using the Google Assistant on a phone, touch and hold the Home button and then click Home button then More and then Account. The account will be selected.)
See documentation at Create voice commands to control online services & devices
It's called Custom Routines in Google Home App.
But it's not so easy to access currently due to unknown reasons.
Switching language to English (Canada) on mobile device does the trick. You'll get then: Routines (incl. Custom Routines), Broadcasts, and even Google Assistant button directly in Google Home App.
Why is it so messy User Experience at Google? Always...