If i format my hard drive while external hd is connected what would happen



hi everyone, this is my issue, i had windows xp on my pc and I wanted to upgrade to win vista, at first I inserted the vista cd and as it went to the process of istalling it came to the section of where to install etc, it gave me 3 drives, my internal drive and 2 external drives that I had connected, at this time I didnot click on anything or delete anythingi turned off both external hard drives, next since I wanted to format my c-drive (internal HD ) I installed window 98 so I could get to dos and use format c: inrder to format my internal HD, as I did this I fogot that my External HD's where conected and turned on , but all I did was format c: then asked me that all info will be lost press yes and so on didnot tell any other drive or letter, there after I put the vista cd where it installed the vista to my c drive (internal HD )., after installation when I go to get the files from my external HD, I cannot, I can see the drives, shows the letter but when I double click on them , state that they need to be formated, I click properties and it states zero free space and zero spaced used, I am not sure what happened here but need help, I donot think I have formated the external hard drives and when I doulble click on them I see the green bar reading on but the format warning does not allow me to get to them, so I am lost here