Online sales: can I allow people ordering an e-book to have it downloaded to their device?
Yes. This may be best done using WordPress and either simple a plugin like this one: EZ PayPal https://wordpress.org/plugins/easy-paypal-lte/ or a full e-commerce plugin such as WooCommerce, see https://wordpress.org/plugins/woocommerce/ and http://www.woothemes.com/woocommerce
We could help setting this up, the minimum time period we charge for is 1 hour for non-members and 15 minutes for members of the co-operative. See: https://webarch.net/pricing. You can join our co-op using this form, if you wish to: https://webarch.net/join