[jamiemcf]

and my friend's PC won't read it. Is there any way for him to reformat it on his PC to make it read/writeable on his PC?

[ibook_steve]

He can either format it as just a normal PC drive (FAT or NTFS) or use a program like MacDrive to access the HFS+ format already on the drive.

Steve

[jamiemcf]

How does he format it though? He can't access it..where does he go on the PC to reformat it?

[seanc]

Disk Management.

It either lives in Control Panel > Administrative tools > Computer Management > Disk Management or
Right click on My Computer and click Manage.

From there you can format the drive.
I'm sure you're perfectly aware, but I'll mention it anyway, formatting the drive erases all of the data on the drive.

[ghporter]

There are also utilities that let PCs read and write Mac volumes. One is Hfsx+. I searched for "pc read hfs+" and got a metric buttload of hits with Google. Give that a try and see what you find.