Spine of the world (more specifically the Silver Marches) would be a good starting point. Given the different types of geography/temperature changes needed it can be difficult to tie the adventure sites together coherently unless you really spread it out across the realms (quite possible given teleportation). While the adventurers may want to pursue the connection between the different Giant modules it would be easier to motivate them using the organizations prevalent in the Realms vs. a single ruler.
Will you be using Eclavdra as written (splinter faction of the Drow) or converting her over to Lolth?
The A series can be squished about anywhere (use Skullport below Waterdeep for A1 and it gives the PCs a reason to have travelled there) in the Sword Coast area. A2 can be dropped anywhere there's a road. A3 gets a bit more tricky with the need for a city but you can always use someplace off the main trade way if you don't want to deal with a city inside a dormant volcano.
Bringing them back to the SotW to kick off the Giants series might take some doing but you could use Silverymoon as a starting point for the G series (with support from Citadel Feldbar and Adbar) - The Glimmerwood would be a great spot for G1 (nice thick forest) and not too far from the Endless Sea of Ice above the SotW mountains (G2). G3 might be a harder sell but you're close enough to Anauroch to drop it on the edge and still keep it in the same neighborhood.
This would place D3 far enough away from Menzobarranzan (sp?) to make it feasible (how many big Drow cities in this part of the world without constant fighting?) but still keep it on a smaller scale so that it doesn't become a world spanning adventure.
The inclusion of a Drow diety other than Lolth will keep the PCs guessing as to who/what is running things...a little misdirection goes a long way and the use of different iconography (think tentacles instead of spiders) will have them thinking it's all about Mind Flayers or Aboleths. Who doesn't love to see people prep for one threat only to find another?
The Forge of Spells is a monumental undertaking of geomantic engineering; Wave Echo Cave is more than just a mine--it is a confluence of ley lines deep beneath the earth. The dwarves and gnomes nurtured these woven nets of energy, capping it with a deceptively simple brazier that, when first created, burnt with great fire.
Its power was manifest, and it was not long until the Wave Echo Cave became a prosperous mine. The items produced were powerful. The Forge of Spells functioned by, in its simplest incarnation, allowed a non-spellcaster to create magic items. Although there was only a single forge, because of its strength, another was not needed.
Using the Forge of Spells when creating magic items has two game effects:
1. You do not have to be a spellcaster, possess spell slots, or know the spell that is required to create the magic item in question.
2. You double the progress made each day when creating magic items.
http://forgottenrealms.wikia.com/wiki/Category:Dwarven_locations might be just the resource you need on Dwarven cities of the Realms. Some have more information than others (its a wiki so that's normal). If all else fails take a map or idea and reskin in with a new name. Unless you tell your players you did it who's going to know.
Depending on the level of magic item creation you are comfortable with (I would recommend not turning the forge into a magical wiz bang factory for balance reasons) you may want to downplay just how much they will be able to create with it. While keeping them interested in the production of the mine can be important it might overshadow any future story lines you wish to explore without you becoming heavy handed (i.e. railroad syndrome).
Good to know. With the need to attune most powerful items and a limit of 3 per PC the accumulation of items shouldn't be the issue it's been in previous editions. If they are unable to flood the market with common items then it won't cause an economic imbalance in the campaign.
Gauntlygrym is the obvious choice, but the Hill of Lost Souls features the tomb of Thelarn "Swifthammer" and is a bit distant from the Savage Frontier, allowing for some travel.Are there any famous lost dwarven mines, suitable for a tomb of a powerful and famous dwarf, besides Wave Echo Cave? I enjoy linking the story to existing cities, if not necessarily people.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.