Robert Allan Monroe, the sound engineer and inventor did a research which turned out to reveal a lot about the soul, afterlife, etc. His intriguing series "Far Journeys" are a highly recommended reading. My mother tried the technology behind his work on herself succesfully. (the purpose was to increase a conscious control over the brainwaves, which worked)

Then, Western esoteric tradition describes the concept of soul very closely, in a quite revolutionary way and compatibly with Monroe. Soul here is described as external, as a "great fiery vortex of energy", having the personality (body, emotions, mind) as it's somewhat detached temporary tool and vehicle for work with the solid-material world.
For that point of view, I recommend the books by Alice Bailey, Initiation Human and Solar should be the safest bet for a beginning. But this is an extensive, more specialized reading.

But what would interest you the most, I already wrote somewhere about the experiments of doctors at the medical university of Munchen, who weighed about 200 patients in the moment of death. There was always measured an exact weight loss, if I remember, 1/3000 of ounce, or something like that. I'd have to search for it again, and I won't have a time for that any soon. You could do it, find my first post about it here (with uncle Google's help) and find a name of a German doctor behind this and exact numbers and dates.
 

I'll make reference once again to our friend Shelly Kagan, who has his lecture series on academicearth.org (with the ominous title "Death&quot. In it, he dismantles the concept of the soul philosophically.

Of course, philosophically is the only way one could ever take the idea of the soul seriously. Otherwise, it's pop-culture nonsense that has stuck around for thousands of years.

In fairness to Plato, it's not entirely his fault. In unfairness to Plato, it's pretty much his fault we still talk about it like it's a topic for grown-ups.

This page on snopes looks good on the 'weighing the soul' thing.

Look up 'out of body experiences' for one of the other the main angles on trying to find evidence for a soul. 

Susan Blackmore has looked into those, and other related things, like Near Death Experiences. I understand she originally started from the point of view that OOBE's may be real in some sense, but ended up very skeptical.

That's definitely something like I was looking for. Thanks.

Also, sorry if the first sentence of my reply, here, isn't making much sense. I'm working off of about 6 1/2 hours' sleep and must go home (still at work, *almost* done.)

Need I point out, however, that Buddhists don't believe in a soul? Secondly- I was looking much more for a history of the soul, or maybe the history of the search for the soul. Will, Bob and Renee gave the best links. BTW- I'm now on part 3 of the Shelly Kagan lectures, and I really am enjoying them.

They don't believe in a soul in the christian sense but some sects do believe in an afterlife per se, with that said they also believe in reincarnation.

Depends on which sect again, that's the issue with this I guess, some believe in an afterlife and/or reincarnation of sorts, and others don't believe in an afterlife or reincarnation at all.

here is the syllabus for this particular series  http://oyc.yale.edu/philosophy/death/content/syllabus

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There are some really great essays in that syllabus (naturlich!) I've been meaning to read Montaigne since I learned about him a few months ago via Julia Briggs' seminal 'This Stageplay World.' If anyone's even remotely interested in Elizabethan/Jacobean English politics, religion, education, entertainment and so forth, I HIGHLY recommend it.

It's one of those 'academic books that doesn't read like an academic book.' And it's been out since '83 (probably in more or less continuous printings) so anyone can get it dirt cheap. I got my copy for $3, plus shipping (from Alibris, so.... yeah, small fortune in shipping- that's how they make their money.)

I'm glad you guys are into that series. You'll find anything and everything you'd need in an apologetics debate there (except , I think, George Smith's argument for strong atheism, which is probably my favourite) and it's done in a very entertaining way.

Unfortunately, Kagan is teaching a class, so there are parts where he's going slowly for the benefit of those taking notes. Fast-forward saves the day in that case.

As for reading material, on the pages where it's listed, that's the material you need for several lectures, like Plato's Phaedo (which is actually pronounced like "Fido", not "Fee-do" ). There's almost no need to read Phaedo. I mean, if you really want to, sure, but I could come up with a bunch of insane arguments for you to read if you really, really want.

I encourage you guys to stick with the lectures, though, even when you're fast-forwarding through parts for obvious reasons. The wind-down is really good.