I have only checked into them, never owned one.
I will say that anyone that has raced before should know better than say that a new chassis is 3500 and then all you need is a few other parts.
How about
body and fitting
fuel system
brake system
safety equipment
electrical
shifter, gauges, linkages, upholstery and paint
License?

http://www.kingchassis.net/Pricesheet.php

http://www.slingshotdragsters.com/kits.html

http://www.swracecars.com/sw-race-cars/new-cars/front-engine-nostalgia-dragsters.aspx

http://www.roadsters.com/ndr/#builders
for more.

Don't forget used...
http://www.racingjunk.com/search?searchString=FED&categoryId1=150


Oh, and since I really shouldn't buy this, even though I want to...(oops, sale already pending)

http://www.jalopyjournal.com/forum/showthread.php?t=403907&highlight=dragster