mass wrote:
Finder doesn't seem to allow me to exclude certain files.
Let's get a few things out of the way first.
As to X1, forget it. It's Windows only, and it's not exactly cheap.
Also, nothing I say applies to Outlook. I assume you're talking Outlook 2011, and I have no clue how it works.
As to Finder, it doesn't do searches. All searches are done by Spotlight. Finder's Find command, the Spotlight menu, these are just different ways of interacting with Spotlight. And, yes, of course you can exclude certain files. You simply have to learn to use Spotlight. I'm not a fan -- I think Spotlight is not a search engine, but a sorry, pathetic excuse for one -- but still, it can do a few things if you handle it right.
Now, about Mail. AFAIK, Apple does not document the <~/Library/Mail> structure, so what follows is from my own observations, and hence not authoritative.
Incoming and outgoing messages from your mail accounts, ie, listed in Mail.app's Sidebar under "Mailboxes", are stored in <~/Library/Mail/[account]>, inside .mbox packages, as individual .emlx files. An .emlx file contains the raw message, plus an XML footer. Any attachments are, of course, inside the raw message in base64 encoding. The .emlx metadata does not include whether or not the message contains an attachment, so you can't use Spotlight to search for messages with attachments, nor can you do that in Mail.
However, messages which are moved from your mail accounts to local, user-created mailboxes, listed in Mail.app's Sidebar under "On My Mac", are treated slightly differently. They are still stored as .emlx files (including attachments) inside .mbox packages, which, in their turn, are inside a directory named "Mailboxes", but the attachments are also extracted to an Attachments directory inside the respective .mbox package, being stored inside directories labelled with the respective message's number. With this arrangement, finding images with Spotlight becomes trivial.
For instance, you say you want to find all images which are not GIFs. In Finder, select <~/Library/Mail/Mailboxes>, then ⌘F or ⇧⌘F. In the search field, type
kind:image NOT .gif
(the Boolean operator NOT is case sensitive). This should find all images which do not contain the string ".gif" in their file name. Of course, there are strings attached. If there is an image named, say, "my_photo.gif.jpg", it will be missed. Also, "kind:image" only looks for TIFF, JPEG, PNG, GIF and BMP formats. It will probably not find RAW images, or those in more exotic formats.
So, your first step in Mail (if you haven't done so already) is to organise your mail, irrespective of attachments, in mailboxes and folders in "On My Mac". (IMHO, this is a good idea in any case.)
The next step is to use a Spotlight search as described above to find all images. After that, it's up to you. I don't know how Aperture works. Maybe you can just import them, or maybe you need to copy them to some folder. (Remember, you may copy stuff from <~/Library/Mail>, but don't move or delete any of it in Finder -- or the wrath of Mac OS X will strike down upon thee with great vengeance and furious anger!) If you do need to copy them to some other folder, I suspect you'll discover another bridge to cross, but we'll deal with that when -- if -- we get there.