A growing number of online stores are adding a Lightning payment option. Although still experimental, this can be accomplished using BTCPay Server. At this moment, it does require some technical skills though.
Blockstream Lightning Store
Lightning Store on WooCommerce
Excellion – Proof of Hat
Empower Your Life
CryptoHO.ST – Bitcoin and LN powered Virtual Private Server (VPS) store
Modular Synth Fun – Audio Samples
If you want to setup your own store and accept Bitcoin and Lightning payments, then check out these resources