A Realtor will be able to provide you with the most accurate information on foreclosures. To my knowledge, all foreclosures end up with a real estate company at some point. As far as how long it takes to get into inventory, I've seen foreclosed homes go on the market after auction within two weeks. But I've also seen some homes taking over a year.
Once again, work with a trusted Realtor. We have great insight on properties then customers may think.