This number is in a scam email purported to be from Ebay saying I had purchased something.

This is a scam.Their unsolicited call claims to be from a PC support company responding to reports of problems with your PC due to internet usage.They want you to give them remote access to your PC to 'fix' it.See --> http://techmysupport.blogspot.com/

I just had "Alex Peterson" on the phone claiming to have recieved information that my computer had errors and if i didnt let them help it would stop working. I stalled for about 10 minutes just for the fun of it. He said he was from "IBO Soft Services" and contact number "(02) 8005 1526".
When i said i would have to give him a call back he hung up.

what could this have done to my computer

I just got a call from this number seconds ago, I told then I didnt have a conputer he then went on to quote me my name and addresss , i said Id call him back ,he gave his name as John Wilkens from Technical support George St Sydney, Indian or Sir lankan at a guess. surley with todays tecnolgy these people can be traced

This is a scam.

Their unsolicited call claims to be from a PC support company responding to reports of problems with your PC due to internet usage.
They want you to give them remote access to your PC to 'fix' it.

See --> http://techmysupport.blogspot.com/

What happens if you enter cmd into run? i did it and the person pn the phone made me enter something in to a black screen with some white writing on it and then i closed it and hung up on them