Corri's list of links is really good. These links are the only place that I know of. I am not sure why you are only looking for Freddie Mack homes because there are actually some very good other bank owned homes and there are even some private and investor owned homes that are really good deals as well. I am a REALTOR in the Klamath Falls area and I would be happy to help. I am not sure if you are looking for an investment type property or a personal residence but either way I can assist you. With many foreclosures, it is difficult to get financing if you need it so there are several things to consider when you are looking at these homes. If you are going to be making a cash purchase then you could have a lot more flexibility and leverage but still want to consider what things will need to be fixed and what those fixes will cost. I have a contractor back ground so I can give you some rough ideas of what needs to be done and idea of what you would be looking at cost wise. Give me a call and tell me more about what you are looking for.
If you are serious I can recommend a local Realtor otherwise if you are just curious check out:
http://realestate.yahoo.com -Here you can search out NOD's (Notice of Default) and foreclosures but when you want more info, such as an address, you will have to pay for it.
Try a few other entities that have assets to liquidate... Here is my list of freebies:
http://cms.oregon.gov/odva/HOMELOANS/pages/properties.aspx -ODVA properties
https://www.equator.com/home/ -VA Properties (and more)
http://www.resales.usda.gov -USDA Rural Properties
http://www.homepath.com -Fannie Mae HomePath Properties
http://hudhomestore.com/HudHome/Index.aspx -HUD/FHA Properties
http://www.fdic.gov/buying -FDIC Properties
http://www.treasury.gov/auctions/irs/index.html -IRS Seized Real and Personal Property
http://www.usmarshals.gov/assets/sales.htm -US Marshall's Office Seized Real and Personal Property