I got an iPhone 5c off of eBay and I can't tell if it's iCloud locked (Activation Lock) or not because I don't have a SIM card for it yet. It was restored by iTunes with no problems. The phone asks me for my language, country, WiFi, then tells me to insert a SIM. Is it going to tell me I need the previous owners password after I get the SIM card and insert it?
Yes, Apple has a very easy page that lets you look up devices by IMEI or Serial Number: