score:11
As a Dane (actually living in Odense), I would use Google (including Google Maps) or ask a local of the city I was in. I would search using Danish terms such as "brugte cykler odense" in Google.
For bicycles, I don't know of any dedicated used bike stores in the city, but from my research, it does seem that a lot of the "normal bike shops" occasionally have refurbished used bikes.
Upvote:5
What was previously the "yellow pages" in the telephone directory exists online at https://www.krak.dk/