How do I know if a runway has REIL?
You can find this information in the Airport Facility Directory which is published in print by the FAA and is available for free from them online here. REIL will be listed for the specific runway for the airport in question. For example I fly out of KDYL and if we take a look at the page in the AFD for KDYL you will see REIL listed for RWY 23

 
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