i just reinstalled the mac ox 10.4 on my computer.....so i lost all my itunes music but before i knew i culd download all the purchases again so i wasn't afraid...but know since the only itunes i have is 9.2 because it doesn't let me have a newer version i click download purchases and it sends me to download 10.7 version of itunes which my computer cannot have....
so the question is how can i recuperate all my purchased music with my account please help
Uh, if you own an older computer you have to learn a whole new set of rules. Rule #1 is never rely upon Apple to in any way continue support for anything older than 4 years so be self-reliant as possible for resources. Yes, you used to be able to download again, but Apple changed things when they they stopped supporting old computers and require you be running iTunes 10.3 or newer to download music (and 10.6 or newer for video).
Even if you write Apple I don't think they can do anything about it without re-loading old software on the iTunes Store. As they say, you should always make sure you back up your purchases. Even if there wasn't the iTunes version issue you still cannot rely upon all your purchases still being in the iTunes store as the distributor could suddenly pull it without notice.
In your case there isn't anything you can do other than install OSX 10.5.8 which will let you install iTunes 10.6.3 (the last for PPC Macs). Either that or find a friend who will let you use their newer computer -- but before you do this, warn them it will lock their computer to your AppleID for 90 days for automatic download purposes.
You would have to buy it. It is not easy to find and the last time I checked it was not cheap. Depending upon your computer model you may not be able to run it, or not want to, or possibly have other options.
Texas Mac Man, Leopard disc sources - https://discussions.apple.com/message/20151842
Get more information about your computer. Go to the Apple in the upper left corner of any window, then "About This Mac". Write down what it says about "version"and report that here. Now continue to "More Info..." Copy and paste the information here, but omit the serial number and Hardware UUID (if present).