I own an apartment complex, so yes I do take my own advise, I'm trying to buy more rentals at the best pace possible.
The best book I've read is one minute to rental property riches , the guy who wrote it lives pretty close to me as well.
You can make more money quicker by flipping properties, but the problem with that is that you can loose serious money if you make a mistake. Rentals are MUCH more forgiving because even if you over pay a little you're still making 50% ROI or so. I've seen people even in my small town make $50k to $200k 'mistakes' on flips during a hot market. Not so much with rentals, even if you pay double what you should, you still break even, eventually pay off your mortgage and then have a property free of mortgage.
The other thing is that in 15-20 years or so, your mortgage will be paid off and you'll have a asset worth tens of thousands or hundreds of thousands of dollars you can sell , refi or what not. Real estate is also the best way to get your tax liability down, my apartment takes care of over 50k of tax burden each year , even though it's profitable.
With a good rental you should be buying at 20% to 35% of market value so you realize a decent bit of equity up front. After 15-20yrs of owning it your initial value should increase 300% to 400% even through crummy markets. Some people i know of will take a $20k property, rehab & rent, get some money coming in and sell to a institution for $50k or so.
Cool! Have you ever heard of David Lindahl? The guy is big time into apartments (and amazing marketer overall). I picked up his book about 1.5 months ago ([ame="http://www.amazon.com/Emerging-Real-Estate-Markets--Coming/dp/0470174668/ref=sr_1_1?ie=UTF8&qid=1312634490&sr=8-1"]Amazon.com: Emerging Real Estate Markets: How to Find and Profit from Up-and-Coming Areas (9780470174661): David Lindahl: Books[/ame]) and I'm just getting started in RE myself (starting w/ wholesaling to get my feet wet; actually have a direct mail campaign going live next week) - apartments (buy & hold) are my long-term objective.