Syncing/External Hard Drive

[sasegars]

I have two questions/issues. I have moved all of my itunes music -- all music files to an external hard drive. When I sync my iphone -- and if I want certain music files to sync from the library -- do I have to move them into itunes on the computer to sync them? Is there a way to sync directly from the external hard drive? My other question is more general. How long should it take to sync the iphone (i have the 3gs). My syncs always take FOREVER. It seems unbelievably long -- I don't know if I have a setting incorrect, if I'm syncing something I shouldn't or what. It's just so long. Thanks for any help.