In article ,
robert bristow-johnson wrote:

i thought (my amateur understanding) the other thing about quasars is that
they are moving away from us real fast, putting them near the edge of our
observable universe (and putting them back in time quite a bit).

Not really. The redshifts of quasars - and thus their distances and
ages - vary quite a lot.

Here's a nice picture that illustrates this:

http://www.2dfquasar.org/wedgeplot.html

taken from the 2dF quasar redshift survey.

You'll see there are plenty of quasars between 2 and 12 billion
light-years away. I don't know why there's an apparent shortage
of closer ones! The shortage of more distant ones happens for
the reason you suggest:

anyway,
wouldn't it take a lot of time for a black hole to get that big, to eat
everything else in reach, etc.? i thought that black holes represented
something more "mature" in the universe than what distant (and young)
quasars would be.

WMAP data puts the universe at 13.7 billion years old - an implausibly
precise figure, but that's what they say! The first stars formed around
200 million years after that. As far as I can tell after a few minutes
searching, the oldest known quasar formed about a billion years after
the Big Bang, with a redshift of 5.82:

http://antwrp.gsfc.nasa.gov/apod/ap000419.html

But, I don't think there are many this old.