As far as I know (and if some intrepid forum member can enlighten us) there is no easy way to create both a FAT32 and a HFS+ partition on the same drive. I found this website with an explanation of how to do it, although, it's pretty convoluted. The link is
here. Also, it looks like you'll need a Windows PC to get it done. It may be easier to not worry about the FAT32 partition, although, it looks like it can be done if you want to undertake the steps.
After taking a look at that article I happened to notice that it was posted in 2003-- well before additional support for PC formats was built into OSX, so that is what one would have needed to do in that time frame.
With Leopard, it is a simple matter that can be done completely within Disk Utility though. It takes longer to describe it than to actually do it!
Start up Disk Utility
Select the drive to be operated on in the column on the left.
Go to the "Partition" tab at the top of the window
Change the "Volume Scheme:" entry via the pulldown menu to read "2 partitions"
Two equally sized partitions will appear in the graphic representing the drive
Click and drag the line between the two partitions to adjust the relative sizes of the partitions until it is right for your use. Click on each partition and you can see the see the size each will be
Click the first partition to highlight it. In the "Volume Information" give it a name and select Mac OS Extended (Journaled)
Click the second partition to select it, then name it and select "MS-DOS (FAT)" in the "Format:" field.
To check one thing, click the "Options" button at the bottom then make sure that "GUID" is selected in the window that appears so that the right type of Partition map is created. Click OK to exit that window
Click the "Apply" button at the bottom of the screen, then confirm your action.
In a short time the drive will be formatted as two partitions, the first with Mac OS Extended and the second with FAT32.
Quit Disk Utility and you are done
EDIT: I just tried this again on a spare drive and it works fine- the FAT32 partition is seen fine on a Windows laptop I keep around for testing and as expected the Mac OS partition cannot be seen.