Probably nowhere, since it's been out of production for many years.
Apple no longer produces a 20 inch iMac. You would have to buy a used one to get a 20 inch model.
You can get a refurbished iMac with full warranty on the Apple website for as little as $999. This is as cheap as it gets for a new iMac. Check the refurbished section and if there is none there check back each day.
Depends on which one you buy. the 21.5" iMac is 18" tall.
It isn't very common that deals and discounts on Apple branded products are available as Apple is usually very expensive for retailers to stock. It is possible that information on discounts and specials can be found on fan websites such as Mac Rumors, and larger online stores such as Amazon may offer discount more often than most stores.
Brand new with free shipping at the Apple Store online it sells for $1199. If you are a student or government worker you can get a discount. The iMac sells for the same price no matter where you buy it. I recommend you buy from the Apple store online.
No, Apple only builds the iMac. You cannot buy all that you will need.
Depends on how old it is, condition, and software installed.
If you are looking to purchase an Apple G5 Desktop computer, you can purchase one from eBay and also Amazon. The price will fluctuate depending on the condition. Mint and unused ones will have a higher asking price.
The original iMac personal computer was the iMac G3. This model was released in 1998 and discontinued in 2003. One can purchase a used iMac G3 on eBay or Amazon.
The Macintosh is a type of computer that Apple developed and markets. Originally launched in 1984 as the Apple Macintosh (often referred to as an Apple Mac) today the range includes the iMac, the MacBook, and the Mac Pro.
There is no 24" iMac. Apple sells a 21.5" and a 27". The fastest 21.5" sells for $1,699. The fastest 27" sells for $2,199. But the 21'5" iMac selling for $1,199 is all the computer the average user will ever need. I have one and it is blazing fast. Faster than any Windows PC I ever owned.
You can buy a refurbished iMac from the Apple store. They're available in brick and mortar stores, and also on their website. They are often at a heavily discounted price compared to new iMacs.