Many people have used real estate to increase their net worth. I have no practical experience with rental real estate, but have found the following resources helpful as we plan to buy or first rental property within the next 1-2 years.
Bigger Pockets is the most comprehensive real estate resource I have found. There is tons of free information available on their website and podcast. They also have forums, networks, and tools that cover almost any real estate scenario imaginable. If you are interested in real estate, I recommend starting here.