Welcome to the Forum! 
Ya what those guys are saying! For the power it all depends on your money. Unfortunatly the allison 5 speeds (which are in all d-max's untill 06) are known to burn the clutches and throw the truck into limp mode when you add 90+ HP with a tuner.
So to start Id do a 4 inch turbo back exhaust, then a programmer, gauges, and possibly a intake.
Then if you wanna go big you'll have to do the trans. Usually the parts alone are $2,000+ to get some decent HP.
Edge is a decent product. If you get that you can save $$$$ on gauges. Also it has lower settings which you can use before doing tranny upgrades.
Also I will have to say if your starting out talk to one of the site sponsors/vendors
