[weld]

I've got two questions about iPhoto, but I don't want to put them in the Digital Photography section because it seems nobody ever looks there. Pardon me for putting them here.
1) I've got 12,000+ photos in my iPhoto library. When I find one I like in the main library, how can I tell quickly which album it's in? I can find out the file name of that photo, its dimensions in pixels, and a bunch of other information about it, but surely it's also possible to find out what album it's in.
2) I want to put the entire library on an external disk which I can then plug in to any of several Macs. How exactly would I do that? What do I need to move to the external hard drive? When I plug the drive in to another Mac and launch iPhoto on that machine, do I need to do anything to tell it to search for additional photos on the external drive? Or will it automatically locate and display all iPhoto albums on all attached drives?
I'd appreciate any help anybody can give me.

[Skybolt]

I'm not at the mac right now, so going on memory here. But you'll get the idea. You don't say what version you are using, but I think my response will work in the latest versions.
1. To find what album a photo is in, you either right click or perhaps command click and it should tell you, I think. If someone else responds who is more sure than I, I will gladly stand corrected.
2. Move the entire iPhoto library to the external. There is an Apple KB article describing exactly how to do this. Then, when starting iPhoto from whatever machine you want to use, hold down the option (or is it command?) key when starting iPhoto and it will ask you what library you want to open. Just choose the one on the external.
I have all my music and photos on an external and it works great!
Good luck!

[Martian]

By the way, moving photos between albums or putting them into multiple albums neither moves them within the library's sub-folder labyrinth, nor actually duplicates them (and of course, when moving a file between folders even in the Finder itself does not actually move it on the hard drive). What looks like files within a given album is just virtual representation. (I wonder if this is what is referred to as a "pointer"?)
In iPhoto, the only time you actually move a photo is when you edit it. When editing, a duplicate file is createdan un-altered version goes into a sub-folder called "Originals" and an altered/edited version then resides where the original had been before you started editing.