how do i move itunes from c drive to d?

iTunes: How to move [or copy] your music to a new computer [or another drive] - http://support.apple.com/kb/HT4527

Quick answer if you let iTunes manage your music: Copy the entire iTunes folder (and in doing so all its subfolders and files) intact to the other drive. Start iTunes with the option (shift on Windows) key held down and guide it to the new location of the library.

The application needs to remain on the system drive.

The iTunes library folder can usually be moved from the current location to, say, D:\iTunes and then accessed by holding down shift as you start iTunes. There are however a few gotchas, particularly for a library originally started back on iTunes 8 or earlier... Are you happy letting iTunes organize your media and is it all inside the iTunes Media or iTunes Music folder now? Where is the main iTunes folder? Where is the media folder? Does the media folder have a subfolder called Music with all the artist folders or are these in the media folder?

tt2