Download past year papers (and mark schemes) for the Cambridge A Level History 9389 here:
This covers the historiography papers. More to come.
Also, check out other tips for acing the historiography paper:
Disclaimer: Do not look at past year paper questions until you plan to use the papers for essay practice. Reading the questions beforehand takes away the element of surprise necessary to make your practice fruitful.
Do not view these papers beforehand if your teachers tell you not to. To do so would harm your own practice efforts and final success. The best time to start using these papers is around March-April.
All the best prepping for your Cambridge A-Level History exam!