http://n2n.org/ or call or visit the following offices (from their website)
In Fort Collins:Neighbor to Neighbor Renter Program at the Murphy Center
242 Conifer Street
Fort Collins, CO 80524
Mon through Thurs:
8:30am-noon & 12:30pm-3:30pm
In Loveland: Neighbor to Neighbor Renter Program & Home Ownership Program
565 North Cleveland Avenue
Loveland, CO 80537
Monday through Thursday - 9am-11:30am & 1pm-3:30pm
I'm sure you've checked out Craigslist, but have you checked : http://northerncoloradorentals.com/? This site has several listings posted by private owners renting their own properties. There are also several property managers: http://www.drakemanor.com/ ; http://hmre.net/ and many others. Just search for : "property management fort collins"
I typically work on home sales (not rentals) but many of my client need temporary housing or my investors need a place to advertise their properties.
Good luck in your home search.