whenever you buy a turbo from a junkyard, it's a good idea to have it checked out and possibly rebuilt.
Either way you're stuck getting a manifold brand new
www.exploitedracing.com has turbo manifolds available.
intercooler try ebay or a junkyard for stuff from dsm's or saab's
the 1g blow off valve from a dsm is a great pick up, also
www.roadraceengineering.com has 1g crushed blow off valves that can handle more than 20psi of abuse...
plumbing you're stuck with handling that yourself, and well your imagination...
for fuel management... well expect to spend real money on new parts there...