well if yer gonna run it all off 1 amp, you need a 5 channel, which really isn't too hot IMO. although I do beleive autotek makes one, its easier usually to just run 2 amps.
As far as sub brands, the audiomobile evo 10 (model #2210 S24 if you're only getting 1) has gotten rave reviews from everyone, I run 2 Evo 12s currently. I imagine the person next to you would hear a bump from this 10, but the majarity of this sub is designed for the inside of the car AKA, it may not be setting off car alarms, but it will give you a nice bump inside and probablly a decent thump outside.
As far as amp, and of course I am abit biased cos I run this stuff lol , but I'd recommend an autotek SX275 or even an SX2150 if yer feelin frisky, either will do just fine, the 2150 will give you more power, so you may get more out of the sub, but its running closer to the subs max power. all of these figures are based on a 2 ohm load from the DVC 4 ohm Evo (bridged parallel)
you can get the audiomobile evo from
www.sounddomain.com I haven't heard of a single person that isn't happy with this sub talking to them
the Autotek amps from
www.thezeb.com
as far as a 4 chan for your door speaks, the only thing I can say right off hand is an autotek SX4160 or an SX480
yea, I'm a bit biased to those 2 brands, but I run em and am very satisfied