Common Hardrive

Hey i was just wondering whether this is possible.

I have one 160 gb I Mac and a 80 gb Macbook along with one 250 gb external harddrive.

What im wondering is... Is it possible to setup one itunes library on the ext. HD. and be have it plugged into my Imac, but also set it as my Macbook's library as well?

I know about library sharing and such on wireless networks but what im really looking for is to be able to d/l music on my macbook, drop it into my itunes and have it be added to the itunes library in the hardrive, which would also add it to the itunes on the Imac.

It sounds rather complicated when i write it out. But to me it seems realistic right?

any way.... can anyone help me out with this?

Nope... you won't be able to do that automatically. The best you can hope for is to keep a common folder of music on the external drive and import it to iTunes separately on each computer. Be sure to turn off the option to copy the music to your iTunes Music folder. As you add more music, you'll have to add manually to each computer's library.