Google Cloud Storage is a great way to permanently store information in the Google Cloud. All you need to do is enable that product for your project, and you'll be able to access Cloud Storage directly from your Compute Engine virtual machines. If you create your instances with the 'storage-rw' service account, access is even easier because you can use the gsutil command built into your virtual machines without needing to do any explicit authorization.
To be more specific, go to the Google Cloud Console, select the project with which you'd like to use Compute Engine and Cloud Storage and make sure both those services are enabled. Then use the 'storage-rw' service account scope when creating your virtual machine. If you use gcutil to create your VM, simply add the --storage_account_scope=storage-rw (there's also an intuitive way to set the service account scope if you're using the Cloud Console to start your VM). Once your VM is up and running you can use the gsutil command freely without worrying about doing interactive login or OAuth steps. You can also script your usage by integrating any desired gsutil requests into your application (gsutil will also work in a startup script).
More background on the service account features of GCE can be found here.