Hello all,
Thanks again for the reply!
@ Xendula : I know I have to deal with it until only God knows when

Thank you for your suggestions. I will not buy books too often, maybe just a couple of times in a year since I still have plenty of books in my computer and I want to read them first. But, if there are books that I want to buy, I just want to know which one is easier to deal with.
@ davidfor : I don't know ebooks have georestriction before I joined this forum. So now, I know

Thanks!
@ llcj : Yes, I checked them out after reading your reply. Thanks!
@ hapmas77 : Thanks! So is it easier to use Kindle here in Indonesia? About 3rd party seller, I'm afraid that will cost way more. I checked them already. I can wait since I'm not in a rush
I have other questions : How to check the book is having a DRM or not? I have some ebooks in epub/mobi and I use my Samsung Tab to read those books and have no difficulties in transferring it. But, will it be easier also to transfer books (either in epub/mobi) from computer to Kindle/Kobo? I heard about this DRM and afraid that after I get my Kobo/Kindle later, I won't be able to transfer the books from my computer.
Once again, thanks for all the reply. I appreciate it so much!