There is a Yahoo! group that is focused on Spokane Area history and frequently has contributions from people who know details. [groups.yahoo.com]
A Spokane area photographer and photo collector named Jerry Quinn has produced a CD of old Spokane area photos. Quality on the CD varies, and details of some photos are lacking, but the photos are there for the taking. You can purchase them at Sunset Junction Model Trains hobby shop (in Spokane) or from Quinn at this weekend's swap meet 2/18 (9:30-3:30) at the Spokane Community College Lair. PARKWATER: Diesel shop still stands but roundhouse is gone. Since the refueling depot opened at Hauser it is only staffed days. The large WFE (Western Fruit Express) shop near the Parkwater fuel rack is a former GN building from Hillyard that was moved to Parkwater in the early 1980's. Havanna St. at Yardley is a good place to watch trains, the cement ramp on the northwest side of the crossing is a place you can park and the BNSF special agents won't bother you. The yard UP uses in Spokane (on the south edge of the Spokane Interstate Fairgrounds) is the former Milwaukee Road Yard built in the 1950's (?) and is in danger of being removed in the next few years. The ex-NP steel depot still stands at Trentwood and is used by the BNSF car department. The ex-NP depot in Cheney (spanish style stucco) still stands and is in use by the BNSF section and signal departments. The NP depot in downtown has been recently remodeled into an intermodal station for Amtrak and Greyhound buses. UP has its 1970's era depot at Havanna and Sprague, it too may not be around to much longer, but for now is still in use for Spokane area crews. The SC&P interurban car barn still stands north of the BNSF tracks, east of the Hamilton street bridge---it is used as a warehouse I think. The former NP produce warehouse still stands next to the BNSF main line (north side of tracks) near the intersection of Division St. and Sprague Ave. It is owned by Washington State University who may tear it down. That's all I can think of off the top of my head for Spokane area proper. In Sandpoint, both the NP and GN depots still stand and are in use by BNSF. The former NP depot may still be slated to be raised to make way for a relocation of US 95 soon. Milwaukee depot still stands as a home in Rathdrum. GN and MILW depot were still standing in Newport last time I checked. NP and UP depots still stand in Pullman, but are no longer used by the RR. WI&M headquarters depot in Potlatch, ID still stands and is currently vacant, a local group is raising funds to restore (maybe). Camas Prairie depot in Lewiston, ID still stands and used as private (Non RR) offices. UP depots in Pomeroy, WA and Colfax, WA still stand. Pomeroy is a dentist office, Colfax is vacant.
I'm just winging it here, so that is all I can remember off the top of my head.