As someone who loves books more than actual people (telling the real truths here), I see book-buying as an acquired skill.
There are certain skills needed to become a thrifty book-buyer, and I am here to tell you some of my tips and tricks that I use myself. And to me, book-buying is one of my most important and favourite things I love to do, so I take it (in all seriousness) very seriously. I have more books than some libraries, and a lot of people are so surprised by that fact, but a lot of it comes down to my thrifty book-buying.
SO, here are some of my top tips!

1) Op-Shops and Thrift Stores (if you’re American…which you’re probably not)
I love myself a good bargain as I’m sure most people do, and Op-Shops are where it’s at. Most people go to Op-Shops for really neat vintage clothing or even just generally cheap clothing which is great, but you will also find some great books! I guess most people view books from Op-Shops as being those with horribly yellowed pages, lots of marks that you wonder ‘is that poop or is it chocolate’ along with cracked spines and ripped pages. While there may be a few of those sitting on the shelves, I also find some great untouched books that I swear have never been cracked open.
Typically you can find a lot of books that were recently turned into movies, some really good children’s books, and you’ll often find books that although look brand new, were probably tossed out because someone needed to get rid of some stuff. This means that you could get some out-of-print editions or rare-finds! I’ve definitely found some crazy stuff that I can’t believe people have tossed out, but I guess one man’s treasure is another man’s poison.
ANYWAY, basically you can generally pick up some great finds for $1 or $2, which is an absolute steal, so you should totally regularly check out all your nearest Op-Shops!

2) eBay, Gumtree and #LoveOzYA Books Buy/Swap/Sell on Facebook
Second to Op-Shops where people are wanting to get rid of stuff they no longer need, are online stores like eBay and Gumtree. Everyone knows eBay, and if you check out newly listed lots of young adult books, sometimes you can find some great priced books that you’ve secretly been wanting for a long time.
Gumtree is even better! I prefer Gumtree because I think it’s actually free for people to list items they want to sell, therefore there’s a lot more people with a larger range of stuff. And it’ll show you local items! People are consistently listing new lots of books, and while some are WAY overpriced (seriously, I’m not going to pay a new price for your books that look tattered and worn) you can totally find some great stuff!
#LoveOzYA Books Buy/Swap/Sell is a group on Facebook where people in Australia often list whole stacks (or maybe just a couple) of books that they’re clearing out, and it’s worth checking out every now and again!

3) Markets and Festivals
Markets tend to be a bit more wishy-washy with what you might find there. But sometimes people just set up a stall as a one-time thing to get rid of all their stuff – like a garage sale! (Which is also a good place to check out) I’ve previously picked up things like a whole box of really good condition Babysitter’s Club books – about 60 of them – for about $4 or $5. You never know what you might find if you actually look! 😉

4) Pop-Up Bookstores, The Book Grocer and Newsagents
Every now and then you get pop-up bookstores at places like shopping centres, or even just around general city areas, and its always worth taking a look. We used to have pop-up stores called ‘Allbooks4less’ which sold mostly $5 books, and while that particular one doesn’t exist anymore (I don’t think), a lot of others surface at different times.
The Book Grocer is a store in Melbourne –  there’s actually quite a few of them! They sell books for $10 or some cheaper price if you buy a lot. They tend to have a lot more adult-fiction than YA, but sometimes you can find some really good stuff there.
While Newsagents you’d think would be an unlikely place to find fiction, depending on which ones you go to sometimes you can find a whole stack of stuff. I’ve been to certain ones all around Australia, and they’ve had chuck-out-bins of stock they need to get rid of for a dollar or two.

5) Book Depository and Booktopia
You’ve probably heard of these two legends! I use Book Depository for when I want new releases or to find older stock. The shipping is always free internationally, and the prices are super reasonable. My tips for Book Depository though are always being aware of the Australian Dollar against the US, because a certain times you can get prices WAY cheaper than normal. My other tips are always putting books in your wishlist so you can get updates of when prices drop, and taking advantage of those occassional 10% coupons you get via email – they make all the difference!
I buy from Booktopia only about once a year, but once in a while I’ll get an email saying that they’ve got free shipping for a limited time, so that’s when I’ll check out their bargain section! It takes a while going through all of their titles in children’s and YA, but I’ve found tons of stuff for like $2 which I never would’ve found cheaper elsewhere.

6) Big W and Target
Y’all know these two. I use these two all the time when it comes to buying OzYA titles. Book Depository coming from the US (or UK if you use that particular site) have Australian titles listed a lot more expensively than if you were to get them as recent releases from Big W or Target. You can often find normal-sized OzYA titles for about $12, and largers ones at $16, which isn’t too bad.
Sometimes Big W and Target also have bargain bins as well, or at least mark-down tags/stickers which is really really good if you come across them! A tip for these two stores is that sometimes although there is no sticker saying a book has been marked down – sometimes titles are cheaper when they’re last-of-stock, but are just sitting amongst all the other books, so it’s worth scanning barcodes if you’re unsure!

OK, so those are some of my top tips for thrifty book-buying! Hopefully you’ve learned a thing or two (or maybe not *looks sheepish*) and let me know what you think!