Some examples of real LaTeX files --- as actually used for APA manuscripts, conference proceedings, talks, and posters --- can be found on dianthus-ficus-croton in the directories
~kruschke/TeXstuff/examples/apa_manuscript/ ~kruschke/TeXstuff/examples/proceedings/ ~kruschke/TeXstuff/examples/talk/ ~kruschke/TeXstuff/examples/poster/