Ready? OK...
There are many determing factors in what you are looking to do and budget, while it may be what you consider to be king, but should be weighed against the cost of what this may cost you later on.
Wiring is a huge one-shot opportunity during new home construction. As in, you can save thousands of dollars in work and headaches by wiring things now, that you may not be able to use for 2-5 years when you can afford the gear, and you can ROLL that cost into your mortgage.
Note: Most home builders are not pros with audio/video at all. Most are extremely bad at A/V and won't have a clue how to answer your questions or to direct you towards solutions which help, and may actually rail against your wishes if it doesn't fit into their limited box of solutions they offer.
With all that in mind:
1. Where do you want speakers? You've listed just a few areas, but why not make the most of this opportunity? Bathrooms, bedrooms, basement, garage (!!!), kitchen, dining room, front yard, back yard, etc. These are all places where people gather and socialize and are excellent spots for speakers at some point. At about $100-$200 per room to wire for stereo, it may cost $2,000 or so to get a dozen rooms wired, but then those wires are there, and are done.
2. Where to wire to? A nice thought is to just wire to your family room. But, if you end up with 10 zones of audio, you may be putting a ton of electronics into your family room. Instead, why not find a good WELL VENTED location in your home where you can run everything to? When I say everything, that means everything! Your home network, cable feeds, telephone wiring, and audio/video lines can all be run to this equipment location. This is called the head-end and having everything in one location makes your whole world a lot easier to manage.
3. How to control the source? Add CAT-5! Your standard speaker wiring should go from the head end to a single gang, low-voltage single gang box in each room, then up to the speaker locations. Add one piece of cat-5 to that single gang box and you can put in a volume control by itself, or put it a IR repeater/volume control system which is more advanced and gives you greater capability in those rooms which need it.
4. Surround zone! The A/V surround zone is not like the music only rooms and you should try to avoid in-wall speakers. Especially in locations anywhere near bedrooms. You can get some decent in-wall speakers, but with in-wall speakers, or worse, in-ceiling speakers, that sound will travel right through to the adjacent room. So, you want to try to go with on-wall rears/surrounds and floor standing front/center speakers as a minimum, if possible. This is not always practical, or possible depending on the room and WAF (Wife Approval Factor).
5. CONDUIT! If you want to minimize your out of pocket expenses today, then leave openings for tomorrow. The best possible solution, which should be done no matter what, is to put in some Carlon Resiguard 1" or larger conduit along critical cable pathways to your head end. For example, in my home, I had a utility (HVAC/Water) closet that I ran two 2" pieces of conduit from basement to attic. This pathway ensures that I can add speakers, network, audio, or video as I need to my head end (basement). I have a separate set of conduit pieces in place between that utlity closet and my A/V head end. Conduit costs about $1 a foot or so, but installation is easy and it is flexible - kind of like a hose on a vacuum cleaner.
6. Equipment: If you don't own it, then this is not the time to think about the actual equipment you want to use in the rooms. Instead, you want to focus on the end goal. Not what exactly will be in the room, but what capabilities you want for each room. Put them to paper, draw up a list, plan your cabling, plan your conduit, come up with ideas while you have open walls and open floors and open everything.
ie (my setup):
Distributed HDTV from single head end
Up to 8 HD sources to up to 8 HD displays (component)
Future: Same, but over HDMI
Basement
Rec room - surround A/V zone
Bedroom - stereo A/V zone
Bathroom - audio zone
Main Floor
Family room - surround A/V zone
Study - audio zone
kitchen - audio zone
dining room - audio zone
living room - audio zone
front porch - audio zone
garage - audio zone
rear deck - audio zone
Upstairs
Master bedroom - stereo audio/video zone
Master bathroom - audio zone (conduit for future video)
BR1 - audio zone
BR2 - audio zone
Big Bedroom (playroom) - Audio/Video zone
Kids bathroom - audio zone
laundry room - audio zone
TOTAL:
2 surround A/V zones
3 stereo A/V zones
13 stereo audio zones
That sounds like a lot, but my home is a pretty standard 4 bed 2.5 bath colonial with a newly finished basement adding a 5th bedroom and a bath to the setup.
The equipment necessary to drive all of this is secondary to my initial planning, but conduit ensures I have access later on, and I wired speakers to all zones with a piece of cat-5 pretty much everywhere.
If you have a basement, and are not finishing it right away, it leaves a LOT of doors open for you.
Remember, wiring external walls usually means there is insultion in the wall, and it is far more difficult, so those are 'must wire' places.
I think I spent about $3,000 - $5,000 on my A/V wiring during construction, but I've more than doubled that wiring on my own since I've moved in and the cost to add that wiring was nothing because I did it myself and had planned for it from the start.
Follow up with more questions, but certainly don't worry about your A/V receiver right now, that's for way down the road.
