If you just want to browse some free listings, Loopnet.com is a good place to look.

I found the site a year or 2 ago and would browse it from time to time.

I have been browsing the MLS database for a few months now strictly searching for duplexes to live in one half and rent the other, but haven't found any I would personally want to live in, and am now extending my search to single family units. 

I have been browsing around on this site for a few days now and I can see how this will be one of the better ways I spend my time.

We are reading the books, listening to BP podcasts, going to REIA meetings, and browsing the BP forums.

@Nate Smoyer, As a customer I found the features to be mostly comparable for my use with innago, tenantcloud and avail. with 60 units at $5/unit/mo, avail would work out to be more expensive than appfolio or buildium. in avail's favor I found the interface to be more polished than innago and more intuitive than tenantcloud.

So I am new to REI, have probably spent about 2-3 months browsing various online forums and searching Redfin, Zillow, etc. trying to get a feel for prices in some areas.

I browsed her website.

I always make sure to put the best selling features in the heading so when buyers are browsing, they see that first.

Was just browsing through the rental adds on craigslist last year and there was my house but with someone else's phone number so it looks like it happens quite often.