After importing content or adding products that are Published, they still do not appear in the main shop index.
This is caused by the Catalog Visibility being set to Hidden by default for some reason. This tends to only happen on imported data or products added before a WooCommerce theme was activated.
Edit the product post and expand the Catalog Visibility link in the Publish box on the right side by clicking it:
Select Catalog/search and click OK, then click Update.