First off, depending on the pressure your pump is going to put out, Toro isn't the heads you want to use. The system I just replaced was almost all Toro and the heads could not handle the pressure, and the ones that could the sleeve on the riser got stuck under the grass. I can't give you much advise on pumps but what I did here was the following:
Layed the piping about 10"-12" below the top of the cut grass. That means if your type of grass is going to be 2" after cutting bury the piping 8"-10" below ground.
Don't be stingy on the piping. Don't buy the cheap pvc, spent the little bit of extra cash and get the thicked walled piping.
Around the edges and especially around sidewalks, driveways and curbs use flex pipe. This is black piping that acts almost like a hose. This way if someone or something steps on it or runs it over with the car the pipe won't break but the pipe will move.
If at all possible use Rainbird bodies with Rainbird Uni-Spray heads. These heads are adjustable and can handle the most pressure a pump will put out. By buying the Uni-spray heads you will save time and money by having to search for only one type.
When you lay it out, try to overlap your spray pattern. It is better to get a little too wet then not wet at all.
If you are going to use rotors, get the Hunter brand. These work the best and they are adjustable to distance and spray pattern.
Installing the irrigation is the easy part, the hard part is keeping it maintained. By running you system on a regular basis and doing a weekly or bi-weekly check you'll save yourself so much headaches and money. After everything is installed make sure you keep some extra supplies on hand to repair when you see it needs it.
Hope this helps, if you have any more questions I'll be glad to help.
Install swing joint at each head, that is: a couple of 90's so you can easily swing the height of your head up or down when installing, replacing, etc.
And install more conductors than you need. The most common problem is a conductor going bad (think thermostat wire). Having a couple of spares going to EVERY valve will save a lot of digging later.
Choose a timer that lets you change the percentage of watering you want. That means that instead of reprograming each zone through the season to adjust for weather, you can just tell the timer to operate at 50%, 75%, or whatever percentage of it's regular program.
If there's a place on your property where you'd like to have a place to attach a hose, this is the time. Make one of your zones go to a hose connection on a post and you can run a wire to a switch on the post to operate the valve for that zone. That way you can also turn that hose on or off automatically to water the dogs, trees, or whatever else. Comes in more handy than you probably realize.
In addition to my other duties, I also run the grounds department for a fairly large school district and we maintain lots of irrigation systems at all the schools and athletic fields.
naysayer, skeptic, conspiracy theorist