Speakers for a 40'x75' room??

You're going to have to get a little creative to do this for cheap (under $1k)

JBL 8128, you can get 8 for $400 on amazon. Very little power required, high sensitivity.

Now the tricky part, getting 8 speakers from 2 channels

This Gemini PA7000 can be had for under $150, it will allow you to hook up cd players and radio tuners, but dosent have any built in.

For an amp this 4 channel ART SLA4 is very nice at $370.

You will need to wire those 8 speakers into 4 pairs (+ to +, - to -) to each channel on the amp for 4 ohm x4.

To wire the pre amp to the amp you would need 2 xlr y cables to split the 2 channels to 4, and then 4 female to male xlr cables to connect to the amp

You might be able to get away with adding one more speaker to each chain of 2. This will make it a 3 ohm load. The amp can handle 2 ohms, but not continuous at high outputs.

If you wire them in series, this will increase the impedance and make it completely safe, but the amp will output much less power

http://www.bcae1.com/spkrmlti.htm

The pre amp is the receiver, it controls the volume. You'll have to find an external fm radio tuner, or get xm radio, or an iPod with WiFi and Pandora/tune in radio apps. Lots of options out there.

What is the budget?
I know Jay1 said under $1k, but I didn't see anything in the original post.

The JBL speakers linked to are 70 Volt and will not work with a regular 8 Ohm amplifier.

I would get a clarification on that. Middle range is nowhere near $1k for 5 pairs of speakers, amplification, volume control and sources plus wire.

So be it.

MY recommendation would be 10 of these http://www.amazon.com/BIC-America-HT...4999837&sr=8-1
8 for the inside and a pair for the outside if this is a covered patio. They sound good and are fairly efficient to drive.

You will need 1 of these volume controls to divide the room into 2 seperate zones (inside & outside). http://www.crutchfield.com/S-rNInrdc...d-SDB-2-1.html
This is the unit that you will control the volume of each room. The receiver volume will be set at a certain level and won't be touched again (hopefully).

This is an impedance matching device so you can feed all 4 pairs into the 1 volume control, while the patio can plug into the second volume control. You will need to set the impdance device yourself by reading the manual.
You can get one of these to connect all inside pairs to the one volume control (just makes things easier). http://www.crutchfield.com/S-HxoJM6j...-VCS-HUB8.html

You will then need to get a stereo receiver, something like this will work http://www.parts-express.com/pe/show...number=252-125

This will feed the dual volume control device I linked above. You can then get a cd player to plug into the receiver for cd playback.

All under $1k plus wiring and labor.

Like this:

Are you going to thank me?

If so, you're welcome.
If not, pffffffffft! !

Make sure that the impedence from each volume control that will be connecting to the receiver is 8 ohms. Otherwise you might overload the receiver and cause it to shut down all the time.
Read the manual for the receiver, it states that if you want to connect 2 pairs of speakers, to make sure that they are 8-16 ohms and to set the receiver to 4 ohms to compensate for running both pairs at the same time.

Get a multi-meter to get a reading on this.

You might need to add a speaker selector between the receiver and the volume controls.