First off, if your rear blocks are 4 inches of lift, you'll want 6 inch coils for the front. This is how most lift kits come, as it levels out the truck as well as lifting it. COntact any lift manufacturer to confirm this if you want. I agree with everyone else on blocks though, that is not to use them unless you're mostly on the street. You can spit em out on the trail, or get that axle hop goin on and break something pretty easily. Check out Sky Manufacturing, they have a shackle flip kit for around 100 bucks, that gives you 4 inches of lift with stock springs, just a thought.
Otherwise, yeah you need the brackets, pitman arm, coils, extended raduis arms or drop brackets for those....get the extended B) Check a website for typical lift components.