Pronunciation

So I realized recently, as I try to hone my Greek pronunciation, that I could not roll my R's. Although this would be considered a speech impediment in a lot of languages, in English there is no use for a rolled R, so I did not learn how to do it. In choir, I remember having to do drills with similarities to a rolled R and I always had to fake it because I could not make my tongue trill.

Over the past few days, based on lots of practice, tongue twisters, and attempts to make my tongue more flexible, I've managed to get the necessary tongue position and make the trilling R noise. Unfortunately, I still sound a bit like either a jack-hammer or a bird because I mimicked those two noises in order to try to learn the trill. Anyone have any tips (I think part of the problem is that I can only seem to do it if I have the air coming from the back of my throat)?

While I was searching around for tutorials online, I ran across this bizarre article which tells of meeting a woman who decided that English speakers are lazy and she was going to pronounce every letter written in every word. Obviously, there a whole slew of linguistic problems with this conception of language. I think English-speakers (and especially Americans) are often lazy...but primarily in their use of descriptive language and expansive vocabulary rather than in their pronunciation.