I think there is some really solid advice on this thread. My two cents:
1) don't purchase property overseas unless you have on the ground knowledge of that country and city and some strong native contacts. You probably would not buy property in Seattle if you lived in Atlanta, why the hell would it be a good idea to buy property in a foreigner country ?!
2) In the US- Don't buy real estate anywhere, unless you have spent a lot of time ON THE GROUND in that city and neighborhood. The numbers often look good in far away cities compared to where you live, but there is always a reason for this.
3) Pick a city or town you would not mind living in and then go there and live there and get to know the market. There are always deals. The secret is not to think of a given city as a monolithic whole, but as distinct neighborhoods, all offering different value. For example in the same city or town, there will be upscale stable neighborhoods, which while desirable places to live are usually overpriced for an investor wanting a decent return. In the same city there will be poor neighborhoods, with really cheap property, which often seems like great deals, but due to the high turn over and crime, often these properties are more trouble then they are worth.
Usually the best combination of return and stability can be found in up and coming areas, but the secret is you have to be one of the early buyers, not one of the masses who buy once everyone knows this is the next “hot” area. That is why its important to be boots on the ground getting to know the city and what is happening. Acting not reaction.
If you are partial to the Midwest, there are a lot of good cities, Columbus, Lexington, Cincinnati, Indianapolis, Pittsburgh and Louisville. Not coincidentally almost all of these cities have decent student populations and a lot of centrally located older neighborhoods that are coming back in style as most people seek to return to urban centers instead of commuting from the suburbs. These older neighborhoods offer excellent opportunities to get larger single family homes (where you would rent by the room) or duplexes, triplexes or quads. These are probably your best bet for a mid range tenant base (students, young professionals) while being in areas you probably would not mind living in yourself and offer good cash flow.
Generally, I feel like non-commercial multi-units (4 units or less) are the best bet for new investors, but a lot of people know this so it can be harder to find good cash flowing deals. Another option you mentioned which has the potential for good cash flow is to buy a large, generally older home near a university and rent rooms. In older cities, which the Midwest is full of, you can often find older homes with 6, 7, 8 even 10 bedrooms. If you live in one room and rent the other 5 out at $400 a month, this is $2000 a month in gross before expenses. If you live there you can qualify for a owner occupied mortgage with less down and better terms or be able to borrow more. The drawback with this type of situation is expenses are higher as you will be paying utilities and its more hands on management.
These are just some things to think about, but you definitively need to do a lot of reading, and do not buy into any of those get rich quick scams. You can make a lot of money, but its hard work.