Where might I buy/stream "Cyber City Oedo 808"?
Haven't seen that in ages! Because it's a little older you'll probably have a hard time finding a place to buy or stream it these days. In the US it is indeed distributed by US Manga Corps. However, their parent, Central Park Media, filed for bankruptcy in 2009. Some of their licenses were sold off to other distributors, but this one has expired and has not been picked up again so far as I can find.

I don't think I have my DVD any more to give you a product number but an eBay search might net you someone looking to offload their copy. Of course, be careful where you buy from as with anything on eBay. The usual places I would go to buy (Right Stuf, CDJapan) did not have it.