Another question:
Will most of the beans I use for my regular brewed coffee be appropriate for Espresso or will I need fairly different beans / roasts?

I home roast with a Behmor and prefer mostly the FC range (give or take).
I may prefer African and Asian beans to the Americas but I'm not sure. I have had some terrific latin american coffees as well. I drink mostly SO as blending in small quantities would be inefficient (unless I blend before roasting).

And finally: though I'm very much a coffee enthusiast, I don't plan on spending tons of time and effort on good home Espresso. I would get good quality entry level equipment ($600-$900 for machine and grinder), read up as I already have, and expect a bit of a learning curve and try to do this right. I don't, however, expect to spend inordinate amounts of time perfecting everything. I realize that this is a forum of the hard-core set, but can a very moderate approach to this be highly rewarding as well (taste-wise)?

I think you may be OK. A Pharos grinder coupled with a Gaggia Classic or Baby class would have you up and running. I don't roast my own beans so someone else is gonna have to chime in there.

Good Luck

Yup. I was thinking gaggia classic or maybe baby class

RE: Washington DC
Went to Perigren this morning, thought my espresso was a bit sour.
Went to Pound on the hill this afternoon and my espresso was quite good.