• For PART-B you can choose aptitude test reference book of P.K.MISHRA
  
  for PART-A only self practise ,no need of any book.

following is the list of the books one can prefer for the clearance of the NATA exam.

• NATA & B.Arch Question Bank  by Ar. Shadan Usmani
• NATA & B.Arch complete self study material: entrance examination by  Ar. Shadan Usmani
• A Complete Self Study Guide for B.Arch by P. K. Mishra
• B.Arch Entrance Examination Guide by Surendra Kavimandan

all the best!!!!