"لَيْسَ عِنْدي دَفْتَر."
Translation:I do not have a notebook.
For laptop actually there is a word but it might be rather long. In ads I guess they mostly use foreign words even if there is an Arabic term for it. For laptop it is حاسوب محمول (Hásúb maHmúl), which means something like carried computer. I think for short they might use the last word only محمول (maHmúl) carried.
Most probably it would from a Persian origin. There is also another word for notebook (or any material to write on composed of paper and grouped together), and that is كَشْكول (kaškúl). Maybe Persian in origin as well.
In classical Arabic, typically (and as per in Quran), a material upon which to write on can be صحيفة (SaHífah) - and this is same as the word for "newspaper" nowadays. And there is also كتاب (kitáb) which is also the word for "book". Also, there is سِجِل (sijil) but maybe this one is more related to "records" than any regular writing.
Absolutely! And much more. It's part of a huge family of cognates and derivatives in an impressive number of languages. Compare these three links:
...and this is how notebook takes us way back to the very beginning of writing. Quite eye-opening, thanks for asking this question.