During the Long Vigil, Hyjal downwards was where most of the population resided - without cities during that era, they would be spread out. They moved to Hyjal to escape the collapsing lands the sundering caused, and based there. It was there Illidan re created the Well of Eternity and Alexztrasza grew the world tree Nordrassil, which Cenarius linked the night elves to and 3 of the Dragon Aspects blessed it enhancing the night elves. There would have their highest concentration
From there, nearby Moonglade became the Order of Elunes centre, nothing extravagant or populous built, the night elves banning arcane magic meant they couldnt rebuild their fallen cities, and their committment to the Long vigil in isolation made the need for a regular civilization like they had unviable.
The druids kept to themselves and the wilds doing their work with the green dragon flight in the emerald dream and the waking world wilds, whereas the priesthood developed the Sentinel and Warden orders to execute the watch against demonic satyr activity and the world threatening use of arcane magic (to the night elves during the era, using arcane magic, their magic, was a threat to the world as it was believed doing so would draw the Legions demons back, so it was banned on penalty of death and all the things they use to employ the arcane for like building cities, amenities etc could not be done. However the arcane was still a part of them, they were surrounded and suffused by its energies and they used the waters to create moonwells to boost nature and the land, heal and cure impurities etc when blessed by the Goddesss as the arcane does enhance nature and is linked with the priesthood and the Goddess too in the night elves - so although arcane practice was banned, the arcane was still very much a part and parcel of their lives and society - and the Well was the most important site they guarded with their lives, as this was the only thing they also knew could be used to call the demons).
From Hyjal they were based, they weren't city civilizations during this era, the druid order had its business sleeping in the wilds thousands of years at a time in Barrow dens all overm the priests made Moonglade their head quarters in the village of night haven, and moved out from Moonglade in hunting parties. Think of mobile camps in constant patrols guarding the land, having stations in key locations all over to guard the forest (not because the forest was sacred and others werent permitted because of its sacredness - that is not the night elf story in warcraft), but because you start getting too close to the well of eternity (this is another area people miss, they think the night elves hated people and the forests were guarded because they worship the wilds, no, no, no, - druids were restoring the destroyed and corrupted forestry and lands from the first invasion, they do love the wilds, as most night elves do, but the reason for the fierce guarding was to stop people discovering the powerful Well of eternity, learning and drawing arcane power and calling the Legion again, like the night elves did. This was the motivation from the priests and sentinels...this is why their lands were no go..not cos they have super xenophobia or blood thirsty.
The druids went throughout the wilds, barrow dens in ashenvale, stonetalon mountain show their activity, dream portal in Feralas and Ashenvale. The night elven female sentinels and huntress would traveling in hunting packs, chasing demons (satyrs) or rogue mages and sweeping the borders as far south as Ashenvale to prevent any race from coming near the well. It is why the night elven sentinels were aggressive and shot on sight orcs and humans in wc3, no one was permitted past those borders, as the Well was a huge secret back then, and as we know, orcs carried demonic taint and alliance arcane users...it wasnt until it was clear the Legion was already here and the Well and world was in danger that forces had to be combined, and the return naturally marked the end of the long vigil.
So you see, they were up in Hyjal and Moonglade, their population wasnt large, but they took their work seriously. They lived simply, out of necessity in order to protect the world, putting aside all the incredible things they could use the arcane to accomplish and improve their lives. Using it during that era could bring the end of the world by drawing the Legion they had ni force to deal with again, and so they would live without its luxuries and benefits of its use they were highly advanced in, nature would meet their needs, the rest would be forfeit. Perfect fir druids, but a sacrifice for everyone else.
Darkshore was uninhabited, ashenvale largely the wilds, a few places spilling down from Hyjal to Moonglade to what became felwood during WC3 is where most things were, Ashenvale becomes populated when they move their capital to Teldrassil, leaving Hyjal and Moonglade to the druidsm because the new city has a a temple, the first in 10,000 years and priests prefer temples to the wilds. Druids do not, the wilds are their home, highborne and arcane night elves prefer cities...but all night elves have an affinity for the arcane, revere the wilds, and desire to live in harmony and peace. Their default nature is benevolent, intelligent and wise. Only in the addiction period did they move away from this core centre, but largely most of the highborne (not all) in particular those closest to the Queen. The Farondis were a zone of highborne in the highest centre of arcane learning and research across the empire they were a highborne group that did not fall to the addiction and hubris of those in the Queens court and were staging a coup to oust her and destroy the Well to drive back the demons..,they were betrayed,and their planned foiled, and in order to teach them a lesson, Queen Azshara destroyed them through a curse of immense power that out them in an un ending cycle of perpetual unliving.