First, welcome to the boards!
Second, I don't have any familiarity with the Mongoose Artificer, so I can't compare it.
That said...
The Artificer is pretty tasty, but its not the only way to get that kind of PC.
1) Any caster can pile up Item creation feats and an arsenal of alchemical weapons, for instance. Don't forget the alchemical items from the Planar Handbook.
2) In addition, the Effigy Master 5-level PrCl (CompArc p30) deals with spellcasters who create various kinds of Contstructs. (I don't have all of the Eberron stuff, but its possible that the Artificer qualifies for it- there would need to be an infusion that mimics Simulacrum.)
3) Depending upon how "open" the campaign is, you might also want to look at the Iron Kingdoms Arcane Mechanik (steampunk crafter mage) and Bodger (quick fix engineer & jury-rigger).
4) In a similar vein, Etherscope offers the Enginaughts (steampunk bionic men & women).
5) Sword & Sorcery's Chaositech is full of fantasy tech that you'd probably love.
[ame]http://www.amazon.com/Chaositech-Sword-Sorcery-Studio-Monte/dp/1588460568/ref=sr_1_1?ie=UTF8&s=books&qid=1253001150&sr=1-1[/ame]
6) In a similar vein, Arsenal and Factory by Perpetrated Press are both out of print, but you may find them inspirational.
[ame]http://www.amazon.com/Factory-Compendium-Computers-Dweoware-Roleplaying/dp/0972135812/ref=pd_sim_b_1[/ame]
7) You might also want to track down Polyhedron #151, which featured a 3Ed Spelljammer mini-campaign. It should have some useful info.
http://www.rpg.net/news+reviews/reviews/rev_6556.html
8) Last, but not least, the games Dragonstar and Dragonmech are both D20 sci-fantasy games that may be of use to you.