I'd suggest you obtain a book from Amazon.com the following book: Ortho's
All About Sprinklers and Drip Systems (Ortho's All About Gardening). It
helped me install my irrigation system on 1 1/2 acres after obtain the
proper permits and supplies. I rented the ditch digger after laying out the
zones I needed + control boxes. The hardest part was using the ditch digger
but that was simplified by some earlier preparation (stakes, string and
laying out my lines). The book will help you determine your needed
supplies, plans, potential problems, etc.. Of course, the first thing to do
is determine what pressure your water supply is capable of producing in
order to sustain the system at needed pressure w/out jeopardizing your home
water supply (thus, the need of a water "well"). However, if you don't have
a week or two off, don't have the knowledge or skills necessary to do the
job, health, etc., then paying professionals to do it right the first time
will be worth mistakes and headaches later on. Get the book first (any home
improvement store should have it) and go from there. The book's cheaper
right now before you pay for a project of this size. Good luck.