The page http://xmlns.com/foaf/spec/ discusses the FOAF vocabularies. Details of the terms are discussed in the same page (e.g. http://xmlns.com/foaf/spec/#term_Person).
But if I am looking for the actual rdfs code of a class or property, where do I get it?
Surprisingly, a web search has not produced anything. The textbooks contain some class and property codes, but they are mostly outdated, as expected.
In the header of http://xmlns.com/foaf/spec/, there are links to the various versions, including links to RDF/XML serializations, e.g. currently:
This version:
http://xmlns.com/foaf/spec/20140114.html (rdf)Latest version:
http://xmlns.com/foaf/spec/ (rdf)Previous version:
http://xmlns.com/foaf/spec/20100809.html (rdf)
As explained in the "Status of This Document" section, you can also get the RDF/XML document via content negotiation:
An RDF/XML encoding of the specification is available by direct link or by HTTP content negotiation from the namespace URI.
And some parts are included in the HTML via RDFa:
The HTML specification no longer embeds the RDF/XML markup; however an experimental subset of the RDF is included in this document using RDFa notation.