Read your local newspaper, the one the notices of default are published in. It's cheap..."free" if you already subscribe to it. It's "safe" because those are legal notices. It's "honest" and "accurate" because, again, they're legal notices.
Here in Colorado Springs we have title companies that provide us agents with weekly updated lists. So, talk to an agent and see if they have access to that. It's actually easier to go through and keep up with than using a newspaper. If that isn't available then I would do the newspaper.
Speak to a local Realtor - ask them to search for bank owned properties on the mls. If you pay for a lot of the services they often have outdated information - the mls is the accurate source for any house on sale in the local market; bank, corporate, builder or privately owned.