I'm a scrapbook paper girl! Around here, Hobby Lobby has an excellent selection. Michael's and Joanns have so-so sections but Michael's supply has literally not changed at all in years. I only buy single pages because the big paper books/sets have so many repeats. Whenever I buy I wait for sales for use 50% off coupons on a single piece of paper. Super cheap but it works for me haha.
I prefer the very thin (like printer paper) ones for general use. They're much easier to keep in place for a seamless curved background and you can stack white printer paper behind them if you need a bit more thickness. I also have a lot of the thicker glitter covered paper. I love it, especially for outdoor or natural light photos! You can get some really cool effects. But since its thicker it can be a pain to keep curved for a seamless background if that's your goal, especially if you don't want to have the paper permanently curved. Holographic scrapbook paper is probably what I'd recommend the least because its a paint (due to being holographic and basically a mirror) but the ones I've found have been thin so they make a great curved surface. They're a LOT of fun but they can be really annoying!
If anyone is looking for backdrops right now, Joanns has a coupon for 7 scrapbook papers for $1!