The other day I set up an Ubuntu installation in a VM and went to gather the tools and libraries I figured I would need for programming mostly in C++.
I had a problem though, where to put things such as 3rd party source libraries, etc. From what I can gather, a lot of source distributions assume that a lot of their dependencies are already installed in a certain location and assume that a lot of tools are also installed in particular locations.
To give an example of what I currently do on Windows, is I have a directory where I keep all source code. C:\code. In this directory, I have a directory for all 3rd party libraries, c:\code\thirdparty\libs. This way I can easily set up relative paths for all of the dependencies of any projects I write or come across and wish to compile. The reason I am interested in setting up a linux programming environment is that it seems that both the tool and library dependency problems have been solved efficiently making it easy for example to build OpenSSH from source.
So what I was looking for was a decent convention I can use when I am trying to organize my projects and libraries on linux that is easy to maintain and easy to use.
Short answer: don't do a "heaps of code in local dir" thing.
Long answer: don't do a "heaps of code in local dir" thing, because it will be nightmare to keep up-to-date, and if you decide to distribute your code, it will be nightmare to package it for any decent distribution.
Whenever possible, stick to the libraries shipped in the distribution (ubuntu has 20000+ packets, it ought to have most of what you'll need prepackaged). When there is not package, you caninstall by hand to /usr/local (but see above about upgrades and DONT do that).
Better, use "stow" or "installwatch" (or both) to install to per-library dirs (/usr/local/stow/libA-ver123) and then symlink files from there to /usr/local or /usr/ (stow does the simlinking part). Or just package the lib for your distribution.