The Factotum is in Dungeonscape, and I don't know about any other way to get the magazine other than downloading it...
But still, a template that reduces HD? how does that work?
I'm not sure if my PC can open Dungeonscape (I have it but I'm not sure that it actually can open it) but I can open it with my laptop. Anyway, when I return to home (I'm at a net cafe right now) I'll check it.
About templates that reduce HD now. You can always apply to yourself the Child Variant template found in D&D Wiki. It halves your HD and reduces your LA by one (at the expense of -2 Str, -1 Int, -1 Wis, -1 Cha but it gains +2 Dex). It also halves the NA of a creature, every countable bonus (DR, SR, Resistances, sensories like Blindsight, regeneration) and worsens the dice of any special quality by one (d8s become d6s etc). You can also cannot gain supernatural abilities at first level (but only at first level, all levels above the first are not affected by it).
I know that it sacrifices a lot but with this template you can have a creature up to 24 HD (considering your LA would be no greater than +4).
@Lurker, I'll check those links.
EDIT: Lurker, your classes are OK, if you of course multiclass out of RoW at 4th level. I don't understand though what the Tome of Necromancy has to do with the game. As I said, no spells. However, since all these are PrCs you can get instead of a spell progression a maneuver progression identical to those of the PrCs presented in ToB.
I only linked tome of necromancy for completeness. It felt bad to link 3/4 of the Frank+K completed works without listing the first one authored. Prelim build:
RoW Aasimar (to qualify for fiendish brute) with the experimental stock background (bite attack, -5' to base speed).
Fiendish Brute 1// True Fiend 1 Combat School[Natural weapons], natural weapons, natural armor, attribute boost (str, con), Sting of the Scorpion
FB 2// RoW Monk 1 Poison Sacs(Quasit Poison), Combat Style (save versus stun, applies to all weapons), Armored in life, Willow Step
FB 3// LT Whirling Frenzy Barbarian 1 Two Weapon Fighting, Pounce
FB 4// RoW Fighter 1 Pincers, Combat Focus
FB 5// RoW Fighter 2 Blitz, Attribute boost (str, con)
FB 6// Row Fighter 3 Large Size, Extra Arms, Problem Solver
FB 7// RoW Fighter 4 attribute boost (str, con), Elusive Target
FB 8// Half Dragon 1 Carrier or Poison Sacs, Scales of the Dragon, Dragon Sight
FB 9// Half Dragon 2 Point Blank Shot, attribute boost (str, con), Wings of the dragon, subtypes, immunities, strength of the dragon
FB 10// Legendary Strategist 1 Huge Size, a world of opportunity
I'm assuming that UA flaws can't be used to get RoW and similar feats.
Flaws: Poor Reflexes
Feats from flaws: Multiattack