June 2019: I came across this page looking looking to get past the 'no module abapi' message on my Mac (in Spyder). This is what fixed it for me: downloaded the 'latest' (not the one called 'stable') version from the Interactive Brokers site and unzipped it. This created a directory called IBJts (it doesn't seem to matter which folder you save this in.) In my case it was /users/myname/IBJts. Then I opened a Terminal session and did:
cd /users/myname/IBJts
cd source/pythonclient #(there should be a setup.py file here)
python3 setup.py sdist
python3 setup.py bdist_wheel #(this will generate a fie called ibapi-9.76.1-py3-none-any.whl in a folder named 'dist')
python3 -m pip install --user --upgrade dist/ibapi-9.76.1-py3-none-any.whl
That was it...then I did 'import abapi' in spyder and it loaded. Now I just need to figure out how to use the package! Good luck...