how do i make "my docs" etc default to another drive

The My Documents folder can be moved to any other location you wish.

Open "Computer", (either from the Start menu, or from the icon on your Desktop if you have one there).

Navigate to "C:\Users\{AccountName}\Documents" where {AccountName} is the name of the Windows 7 account you are logged in to.

Right click the Documents folder and select Properties. In the "My Documents Properties" dialog window select the "Location" tab. You can specfy where you want to move the folder to here.

Do the same for the "Downloads" folder.

Be careful! I wouldn't move them to any external drive. Also, if ever you reinstall Windows 7, that will re-create the My Documents folder in the original location and attempting to delete that and use your preferred My Documents on the different drive may cause problems.

More detailed guidance here;
http://helpdeskgeek.com/windows-7/move-the-my-documents-folder-in-windows-7/

Hope that helps.

Mark

Right-click anywhere on your desktop and choose Personalize.
Click on "Change desktop icons".
Put a checkmark in "User's Files".
Click on the OK button.

This will put an icon on your desktop that will have your user name. Click and open it. All of the files in here can be changed except for two: AppData and Tracing. All of the other files can be changed by right-clicking and chosing Properties, and then click on the Location tab and type in the new location.

If you need to partition your hard drive to make another drive letter, you can download Easeus Partition Master Home Edition here on C/Net Downloads at:
http://download.cnet.com/Easeus-Partition-Master-Home-Edition/3000-2248_4-10863346.html?tag=mncol;2 Then you can shrink down the C:\ drive and create another disk drive with that program. Then, I would create the folders first before you try to move the locations.