You can in Guatemala and other "less developed" nations. I live in a Mayan village on the shores of Lake Atitlán where I estimate around 75-95% of the houses were built by unlicensed builders.
That means that many of them are either unsafe, unlikely to last very long or both, but few complain about this because they're likely responsible for it and moved here precisely for the
freedom of building where there are no building codes and licensing. Many of them are also well-built and beautiful, and proof that almost anyone can build their own house.
I got into the building trade here first building my own house then being asked by neighbours to build theirs. I learnt from carpenters, masons, general contractors, architects, engineers, geologists,
local natural builders, random crazy inventors and anyone else who had something useful to share - some were local, some from other countries. I also learnt a LOT from
books and the Internet, although it has been tricky at times to understand more complex subjects. Fortunately the freedom to make mistakes, and the demand for builders here, has meant that I've also learnt a great from simply having to find a way to do stuff that back in the UK (where I'm from) there's no way I'd have been allowed to go near.
I think if you're conscientious about doing your homework and have a tendency to over-engineer the important parts, that it can be a great education in building and I've now hosted a dozen natural building interns who come here to get the degree of exposure to building that would be a lot harder to find in their own countries. I realise this
thread is a little old but if you still feel like a break from all those authorities, inspectors and codes then maybe save a little cash to get you started, and head south to where you can find an abundance of clients and building projects to cut your teeth on.
I started building my own house in 2005, then built my first house for a client in 2009 and if you're interested in what I'm building now then take a peek here:
http://returntotheforest.org/projects/
I should also add that this sort of exposure and learning isn't a substitute for a more thorough education from accomplished masters, but if that's difficult to attain then there are alternatives in places like this. There are also many excellent natural building schools and courses throughout central and south America, not to mention elsewhere in the world.
Charlie Rendall - http://www.returntotheforest.org
Bamboo Builder & Director of "Return to the Forest" courses, Lake Atitlán, Guatemala.
Living in the land of eternal spring: 1600m altitude; tropical highlands with warm rainy summers & warm dry winters; lots of corn, beans, sweet potatoes, avocado, coffee, hog plums, citrus, bananas and bamboo.