make in the port tree: where can I find documentation?

[sebovick]

Hello,

I'm a long time user of BSDs, and I don't find man pages or 
documentation on the way I can master the port collection (specialy the 
fonction of make).
I found this, interesting: 
http://www.freebsd.org/doc/en/books/handbook/ports-using.html, but some 
interogations persist.
I search a command that list all availables variables that afect program 
installation, and all arguments I can give to the /usr/port/Makefile  (I 
know about 'make search key= and name=' is there another?).

Could anyone give me some cool addresses to learn on the subject?

Cordially

serre.bx at gmail.com