[vash]

mikester is right on. you need to buy a cheapo pressure gauge to check psi with gallons per minute. then you can find out how many heads you can have on a circuit. then you need to lay out the heads, remembering that every sq in of lawn needs at least two heads hitting it. overlap is key to green goodness. then stake and paint out the planned layout, and call USA (underground services alert) to check if there are any utilities in the way. FREE! and mandatory by law.

THEN RENT A TRENCHER! i paid $120 a day, and used it for 4 hours. laying out the pipe and heads is cake. there is a "scissor" that ratchets thru the pipe with ease, cheap. and the rest is glue fun. putting down the system was fun.

as far as hooking up to the water supply. it needs to go in after the meter, before the house shut off. hopefully there is a tab there. if not, you will need to do it. hire a plumber to do just that part if you are not comfy.

the freezing part is foriegn to me. nor cal doesnt freeze. my guess is that you will just have to go deeper below the frost line, but i am guessing.