he someguy try right clicking on your d drive in my computer, click format, check these options
capasity: wotever, i assube 10gb
File system: ntfs
allocatin unit size: 4096 bytes
then check "quick format" and press start (it will only take at most 2 mins as it isnt overwriting all the data on the disk).
if you have data on the disk i am pretty sure its gone, however you may be able to use a file recovery program to restore some of it (http://www.pcinspector.de/file_recovery/UK/welcome.htm is a good one) but i wudnt be to hopefull.
if this wont work i would reccomend using some software like partition magic to merge your d drive eith your c drive and then split them into 2 again.
hope this helps, u can talk on msn for more help if thats less difficult. :),ben