I would say that is 3 different groups - possibly you could limit it to 2;
For architecture you want a good wide angle lens - that is a short forcal length. I know less about the lenses on offer in this department and less about ones that would suit architecture best - but a wide angle for certain
For people can we clarifly - do you mean people as in portrates or in a more generalist sense - like walking about (street photography) and such?
For closeup you want a good macro prime lens - there is a good range on offer in this area and if portrates are your interest I would recomend either the Nikon 100mm micro VR or the Sigma 105mm macro - both of which would be good macro lenses and also good portrate lenses as well. The VR (vibration reduction) on the nikon lens would be a fantastic aid when using the lens for normal (and portrate) uses - for macro work its has less of an impact
If your not into portrate work the market opens up a bit - there are shorter and cheaper options, good for static subjects, but not as good with things like insects where you want the longest focal length you can (so as to be be able to put as much distance between you and the subject as possible); lenses on offer are:
Nikon 100mm macro VR - good solid choice of lens and the only macro lens with vibration reduction
Sigma 70mm macro - short and sharp - possibly sigma's sharpest lens
Sigma 105mm macro - much like the nikon, but without the VR. Note that this and the 70mm extend as they focus.
Sigma 150mm macro - This and the next sigma lens are the top quality offers from sigma- offering teleconverter compatabilty, internal focusing (they always remain at the same length) as well as better build quality and HSM focusing motors.
Sigma 180mm macro - Much like the 150mm lens in features, however this lens is generally considered a bit too heavy for prolonged handheld use and is better used on a tripod setup.
Tamron 90mm macro - a good sharp macro lens and also the shortest recomended lens for insect work.
note Nikon call macro micro on their lenses - the words both mean the same thing