Well, that depends on what constitutes ‘new’ in your view. There’s still lot that will be familiar to you, but many mechanics are changed to take the 3E mechanics into account, and there’s a host of new feats, the noble class, the 3E magician class etc.
That said, many of the regular members and moderators here have a firm grasp of both 2E and 3E mechanics and you’ll find people here who play 3E as well as those who vehemently stick to 2E and then of course there are the people who basically houserule everything or use a different system (or parts thereof). At least in my view, all share a deep affection for the flavour and richness of the setting and this takes precedence over the mechanics used - if you want to discuss your GURPS or Palladium adaption of BR, feel free - diversity is always welcome.
I can’t really help you with your second question, I haven’t checked out the pdfs, but if you’re still in need of 2E material, I’d recommend trying ebay - at least here in Germany there are quite often offers and they sell comparatively cheap - compared to planescape, for instance.
Yup, so long as you love the setting, you’ll fit in here regardless of ruleset. Many people made the jump to 3E. Some still prefer 2nd Ed. Then you get the few oddballs like myself who have adapted Birthright to Castles & Crusades.
Alas, i can’t help you re Paizo either. Though personally, you might want to see if you can find yourself the original boxed set on eBay or something. Usually plenty of good material available there nice and cheap. Then you’ve got the hardcopy.
Hmmm, I thought I posted this earlier but it seems to have vanished.
While I don’t have the main book from Paizo I do have several of the other books (Book of Magecraft, Cites of the Sun etc) and they do feature all the warcards and maps and cardstock inserts however the entire thing is just a scan of one page after another, so the quality isn’t that great and there’s no PDF index. So if you don’t mind printing out all the warcards and pasting them onto index cards, and having them a little fuzzy you’ve found a much cheaper way to get a hold of them.
If you’re just looking for the setting/domain information, the expansions at Paizo are a great deal at only $4. (I also found them several other places for $5)