Your personal data will not just appear on your new computer. You must put it there by transfering it from the original computer. These Apple KB articles will help you:
Thankyou for your response
Forgive me as I feel I didn't explain myself well enough, I was under the understanding that by purchasing itunes match my entire library would become available in the cloud using my apple id, using this id on my new computer locates my library but will only show purchased songs, all my cd's I burnt to the first computer are nowhere to be seen. Now I've tried to download the latest update on the first computer but am unable to. Im at a bit of a loss as my ipod classic has so many songs on there but if I want to add new ones i'm having to go back to the first computer to purchase any new ones, if i sync the ipod to my new computer it wipe my library and only show purchased songs. I apologise for the long winded explanation but I'm having a nightmare with this
thankyou in advance
You are not understanding how all of this works.
Yes, iTunes Match will allow you to have access to all of the music in an iTunes library from almost anywhere. However iTunes Match must have music in the iTunes library when the service is activated. If you activated the service on your new computer, and there is no music in the library, of course you will not see the music from the original computer.
As I said in my first post, your personal data from the original computer will not magically appear on the new computer. You must put it there by transfering it. iTunes Match is not the best way to do this transfer for music. Now, if you wish the music from the original computer to show up in the cloud you must enable iTunes Match on that computer as well and let the service complete its scan.
About the iPod: an iOS device can only be synced to one iTunes library at a time. When you connect it to an new computer for the first time all the entertainment media and apps will be deleted and replaced by what is in the new iTunes library. So, to make sure you have all your personal data, again, copy the entire iTunes folder from the original computer and place it at ~/Music/ on the new computer the launch iTunes.