Google Maps will allow you to find what's left of Centennial

https://www.google.com/maps/place/Orchard,+CO/@40.3300356,-104.1191824,314m/data=!3m1!1e3!4m2!3m1!1s0x876c2eeb67cfc90b:0x3299cd7ae2e3c471

The above link will allow you to see what left of the Centennial set. It is located on Grand street, I would suggest zooming in and using the "street view" option. It appears to have actually been incorporated into the town of Orchard Colorodo. The side of the street across from the spot where the saloon stood, it's no longer there, still has most of the buildings, including the Sheriff's office standing. These set locations have actual numeric addresses and although most buildings are in poor repair some seem to be used.

For fans of the show, if you remember the scene at the end of the 7th chapter, The Shepherds, in which the Sheriff walks away from Lloyd and Brumbaugh it will help you identify what is left standing today. On the left, the only structure I recognize is the livery stable. The front has been slightly altered but the main body is the same. On the right the first building is, in the show, a two story building but now is only a single story building. The faux top must have been removed but the bottom remains. You can still see the distinctive and ornate posts that support the overhang. Further down the street, on the right you'll find the Sheriff's office and the meat market Mrs. Wendell was exiting in the 8th episode, The Crime when she called her son over to her. The streets wood sidewalks have been replaced with more modern concrete ones.

I've wanted to visit the sites where Centennial was filmed since I was a kid when this first aired. Hopefully I'll get there before all the sets are gone but at least Google mas let's me have a peak.