"there's absolutely no development or hooks to get this thing off the ground!"
sigh, I guess those who have only played later editions need to be led by the nose (both dms and players)! Ok, tell your players that theres this funny looking old human sage smoking a pipe who tells them that this is their assignment...
"I mean, I can't figure out why the players would even hang out in Hommlet long enough to actually learn of the adventures."
Its on a caravan route to and from the wild coast and verbobonc. The PCs could be part of a caravan that stops here at the inn of the welcome wench. When they check into the inn, there about a half dozen npcs at the Inn (furnok, turuko, zert, spugnoir, elmo, etc.) who could spill the beans about a ruined moathouse with varying motives.
If a PC is a cleric of the Church of St. Cuthbert, he could be assigned to Hommlet or he could have a dream that intimates that he should travel to Hommlet and investigate 'resurgent evil' or 'the second rising of the temple'. A druid PC could have a similar assignment/dream set of options but he can deal with Jaroo.
A fighter or ranger might get an urgent summons from his uncle 'Black Jay', who wants his nephew to help 'set the region aright again'. Black Jay could provide logistical support but claim he is too old to take an active part.
Good or treasure-seeking PCs can hear of humanoids raiding the caravans and decide to go and stop such mischief.
In two minutes, Ive come up with a half-dozen or more scenarios with an easy 'hook' into hommlet or the moathouse.
"Also, there's all this contradictory info; the siege of the ToEE happened a decade ago, but now it's location is lost?"
How is this contradictory? It happened several years ago and every idiot in the village knows that the Temple is NEAR Nulb but since the average townie never entered the actual Temple, how would they know EXACTLY where the Temple is, except that its in the Gnarley Forest near Nulb. They'll suggest going to Nulb and asking one of the treacherous locals for the location.
If you need to be led by the nose, the path goes inn of the welcome wench to the moathouse, lareth's papers and interviews with burne and rufus lead to advice to go to Nulb, which leads to leads to the actual Temple if the PCs do any reasonable information gathering or pay up some bribes at one of the disreputable establishments in that town.
"Now I don't want to bash it, and I certainly don't want to get into a debate about editions. I guess what I'm trying to say is: I feel like I'm trying to drive standard here, and I've only ever ridden a bicycle."
It does seem like you are used to riding the elminster bicycle.
"So on to a constructive thread: How have you actually used this baby in play? What do you use for hooks, and how do you connect the locales?"
Sure, many times in different campaign worlds, with different alterations. It depends on the party's motivation. Think. If a PC is a priest of St. Cuthbert, then use the Temple or divinations as an information source. If a PC is a druid, use Jaroo the same way. I mentioned relating to Black Jay. I mentioned teaming up with one of the half-dozen npcs in the Inn. One neat twist is from the TOEE videogame -- have Lareth SURRENDER if the PCs are kicking ass in the moathouse and offer to lead them to the Ruined Tower where a secret entrance to the dungeons and riches below the temple await -- then have Lareth be a totally faithful party member for a while until he leads them into the brigand trap or into the werewolf trap below the ruined tower!! If a PC is hanging out in Nulb and is a decent thief or of neutral alignment, have one of the four elemental temples try to recruit the party member and use them in secret missions against rival temples, since no one will be able to connect the dots between an outsider and their source. There are dozens more 'hooks' in each phase of the module that are equally obvious depending on the characteristics of your party.