Recent Henry Yee eBay auction questions

[obcbeatle]

I recently received an email from Net54 or a Net54 member regarding the Henry Yee eBay auctions this week. I don't collect old photo's per se but took a peek at most of the photo's, photo slides and photo negatives in Yee's auction and was astounded at the quantity of nice photo's being auctioned, and also the prices being paid for these photo's! My questions are:

1) Is there a good online resource for better understanding the hobby of vintage baseball photo collecting? I saw the Fogel/Yee book on Amazon but it's over $40 dollars and I'm not sure I'm ready to fork over that amount yet since I'm just beginning my research into this area of collecting.

2) The prices I saw paid for some of Yee's slides and negatives seemed awfully high to me. Do/can buyers turn around and reproduce photo's for re-sale from these slides/negatives? It looked like most of the slides were originally from famous photographers. I'm just curious because I have an old slide projector and thought I would bid on a few slides only to find out that they were being bought at much higher prices than I expected.

3) Is vintage sports photo collecting increasing dramatically as a hobby? I saw an online PSA article that implied that it is, but PSA is in the business of trying to authenticate sports memoribilia. So I suppose it was a bit of a biased article.

I've been collecting baseball cards for many years and only have a couple vintage baseball photo's. I really like the old photo's, but I'm not sure I'm ready to add them to my collecting habit just yet ... thus all my questions. Any comments appreciated.Thanks!