Hi @Austin_Gammell,
I believe the Slack integration is a built-in functionality and should be available with the free membership. At least, the documentation does not mention the need for a PRO account. You should be able to ‘Send Airtable updates to a Slack channel’ with this integration.
I would recommend that you try it out (https://airtable.com/integrations/slack/configure) with your free membership.
If you want to create Airtable records from Slack, then you would need a Zapier integration, in which case, you would have to pay for a Zapier membership.
Hope this helps! Let us know how your workflow organization goes.