Karina, generally speaking, you don't really need bilingual books--you just need books in the minority language, in Spanish. Maybe your local library would even have a section of children's books in Spanish, or would be willing to start growing one? Although I've built up a large home library of books in our minority language, over the years, it's also true that I've taken full advantage of the collection of minority language books available at the library in town.
As for obtaining Spanish books online in thrifty ways, I invite others out there to offer suggestions!
Adam Beck is the founder of Bilingual Monkeys and The Bilingual Zoo, and the author of the book "Maximize Your Child's Bilingual Ability", praised worldwide by parents and experts in the field. Available at Amazon amzn.to/22XKuCt, the global Amazon sites, and other booksellers.
I have had some luck using "Craig's List" type sites in Spanish speaking countries. Just like in the U.S., you find people looking to unload their children's libraries after their kids have moved out. Usually the exchange rate works in your favor. The problem, of course, is shipping. If you have relatives or friends in a certain country, this can be negated somewhat by having them pick up the books and packing them in their luggage next time they are in the states.
The cheapest way is to borrow books from public libraries. You can keep them for several weeks.
Another way, if you have family overseas, ask them to buy some books for you, and bring them when visiting.
Also, the public libraries, at least here in Arizona do many book sales where you can get books as cheap as $1. Also, find out which libraries in your city offer bilingual (English-Spanish) story times. In some special celebrations they give away books for free.
Check also some Baby/Children yard sales on FB; you may find some in there too.
I have a friend who is a school teacher, and she can buy some books for me on Scholastic with a special discount for teachers too.
Half Price Books, if it exists in your area (I think they cover most if not all of USA) have a children's foreign language section. Even in the middle of monolingual Iowa I managed to find quite a few Spanish books there. It's usually right next to the kid's section, and separate for the adult foreign language section.
You could also try to exchange books with other bilingual families you know. I have mentioned this to my friends but so far we haven't got around to doing it. Books are fairly expensive in Spain plus they often tend to sell hardbacks (which are more expensive). I don't think half price bookshops exist and where I live there aren't any second hand bookshops...but try secondhand bookshops and charity shops too. I got my books mainly from Amazon as where I live there is little choice in minority language books especially children's and they are more expensive but am also starting to look at Ebay. Are there any other UK online discount bookshops that I could order books from? Even starting to consider buying a Kindle/Ebook as you can download many books cheaper (although I prefer the traditional books!).
Also, if your children are young and can't read yet, you can just use your English books you have and translate or make up the story in Spanish. It's just about them hearing the story in Spanish and the pictures helping them to understand what's going on and learning new words. Sometimes I shorten stories when reading in English to the kids...but of course I get caught out sometimes lol. My daughter is like, hey, you skipped when X, Y, Z happened!
Wojtek: Mayken: Thanks! That kindergarten is far better then the last one. And we all love it. English has time frames everyday. It is not like they communicate with children in English throughout the day but it's the best place in our region.
May 11, 2017 17:52:03 GMT 9
Wojtek: 1st week's gone. Tonight when we sat in the dim light just before getting to bed she sang the song for me she learnt in her new place. It was like: "I love my daddy. Here's a kiss and a hug for you. Thank you daddy for all you do". I wept...
May 13, 2017 4:51:38 GMT 9
Adam Beck: Ahmet, I'm so glad you're enjoying it! Your positive reaction (including your fun photo) means a lot to me! Many thanks!
May 13, 2017 22:19:28 GMT 9
Amy: Wojtek, enjoy those magical moments. You are a very lucky Daddy.
May 14, 2017 1:09:34 GMT 9
Wojtek: Amy: Thanks! I am a very lucky daddy!
May 15, 2017 22:50:12 GMT 9
Mayken: My daughter brought her ml workbook home recently, and that inspired me to create my own worksheets for her. I posted them on my blog: http://www.cow-pla.net/wordpress/tag/work-sheets (Don't be too harsh on my drawing skills, please. )
May 19, 2017 5:21:25 GMT 9
Adam Beck: Great, Mayken! And I bet your daughter enjoyed your cute, creative efforts!
May 19, 2017 6:14:32 GMT 9
Nellie: My daughter has started asking (in ML/Spanish) for me to sing her songs in ml2 (English)! Several times today and yesterday she asked for "la canción en inglés", while just a month ago she would scream if I did so! This seems like progress!
May 20, 2017 10:00:13 GMT 9
Adam Beck: New video at Bilingual Monkeys TV: How to Get Your Bilingual Child to Speak Your Language (Watch at my YouTube channel, and please subscribe for more videos!) https://youtu.be/YrBUH4UJEGU
May 20, 2017 15:54:56 GMT 9
Amy: That is amazing news Nellie!! Go for it!
May 20, 2017 21:24:10 GMT 9
Mayken: That's great news, Nellie!
May 23, 2017 4:43:34 GMT 9
Adam Beck: Nellie, yes, this is an excellent example of progress! Good for you both!
May 23, 2017 5:58:08 GMT 9
Adam Beck: NEW VIDEO with my cousin Andy! I hope you like it! (And please "like" it, if you do!) Funny Tongue Twisters for Kids (and English Learners of All Ages)https://youtu.be/lsGkJcJj7a8
May 24, 2017 11:53:48 GMT 9