have you got a cd-writer?
browse for this folder to see if it is there: C:\Windows\Options\Cabs.
If possible burn that folder onto a CD. Voila. Full win98 install CD.
To get the product key open up regedit: Start>Run>(type 'regedit'). Locate the key HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\Current Version\ProductKey. There you should have the 25 digit product key to enter when reinstalling.
There you go. Full version of Win98 on a CD, which you paid for when you bought the computer, even if they didnt give you this installation disk.
<font color=red> -- </font color=red><font color=blue>A bush in the hand is worth two birds at the bar</font color=blue>