include/exclude tutorial

[Imbaud Pierre]

Maybe I am tired. I have been reading man page, and these messages, and 
the website, I just dont understand how include/exclude works.

Is there a decent tutorial on the subject, I missed, for some reason?

all I want is to take /var/tmp/*.conf files. I dont want to recurse down 
thru directories (but, for reasons hard to explain, I must have the 
recursive option on)

Reminds me when I tried to understand the find -prune option. I never 
succeeded.

Or should I proceed empirically, preparing directories, and trying 
combination?

And please tell me, those who master the include/exclude technique: how 
long did it take to reach full understanding?