Aptitude is an enhancement from ToB. It lets you apply feats that affect a single weapon to any aptitude weapon.
Crossbow Sniper is from CW, I think, or CAdv. It allows you to add 1/2 your Dex to your damage roll.
Hit and Run Fighter (the Drow fighter sub-level which does not require the Drow race at all) is in Drow of the Underdark, it allows you to add your Dex mod to damage against a flat-footed enemy within 30ft.
Targetteer Fighter is from Dragon Mag (somewhere, look in the Crystal Keep class index.) It allows you to add your dex to damage as precision damage.
All these bonuses are different types, hence, against a flat-footed enemy within 30ft you could get 2.5x dex to damage. Since you're a totemist, your Stealth COULD well be through the roof, since tons of things improve Hide and Move Silently.
A good race is any that has a dex bonus but no CON penalty. Human works fine, Azurin, too, for the bonus feats, and bonus essentia in addition, in the case of Azurin.