If that's the extension for Scancat Lite Plus files, that software is generally considered to be a real POS. While there is a Scancat Yahoo group, I don't know if any .rsd files would be found there.
Your much better bet is to utilize the resources listed in our Scanner Programming FAQ, which is listed here...
http://wiki.radioreference.com/index.php/Scanner_Programming_FAQ
(anything in blue - my machine here at work shows purple sometimes - is a link)
Basically choose the right software for your scanner. Then see if there's a Yahoo group for it, or for your scanner. Also check to see if there's a Yahoo group for your area, and don't forget that with a premium subscription you can build your own files from the database. And, of course, request a file on your state's forum here.
This is all basically explained in the FAQ
73 Mike
