With the advent of this group, I decided it was finally time to buy a copy of Ladefoged. I also ordered a book on the phonology of Old English stress and metrical structure.
Ladefoged came today. The other book is on back order. Anyway. I've only leafed through the book, but will be going back to it over and over again. This is the first time I've ever seen it. I'll probably bore all of you with my questions and comments as I assimilate his lessons. I will say the book meets my criteria for what a US college Freshman could (or rather, theoretically should be able to) handle. Even an advanced, motivated 10th grader (16 years old) could manage this one. Ladefoged is very clear, and seemingly, leaves nothing unexplained.
My first questions concerns glottals. On p. 52 of my text, Ladefoged writes:

One of the most common occurrences of a glottal stop is in the utterance meaning "no", which is often spelled "uh-uh". If someone asks you a question, you can reply "no" by saying [ˈʔʌʔʌ]. Note that there is a contrast between the utterance meaning "no"and that meaning "yes" that is dependent on the presence of the glottal stop. If you hand meant to say "yes", you might well have said [ˈʌhʌ].

I'm pretty sure I know what a glottal is, and am pretty sure I can do one too -- but let's make sure. Following his example of making a cough was not particularly useful (I'm a heavy smoker, if that means anything here). My question, then, is about the fact that Ladefoged's examples can be reduced to a grunt, with the mouth quite tightly closed. Nonetheless, I can feel and hear the difference between the yes-grunt and the no-grunt. The yes-grunt is smooth, while the no-grunt has a very brief cessation of sound initially and in the middle. It's a glottal even at this reduced stage?
I'm pretty sure I've got it right. Getting into Rs, though, is going to be difficult, I think.