Salam,
English:
1."Exploring the world of English" by syed Saadat Ali Shah
2. "A practical english grammar "by A.J. Thomson
3.Ilmi Test paper for B.A English
4.Chamber's 21st century dictionary
6.Some good urdu to english dictionary for translation (Feroze sons' dictionary is a good one)
URDU:
1."Urdu General " by Sohail Bhatti
2.Caravan "Urdu" by Khalid Naeem Khan
3.Caravan "Urdu Advance " by M Imtiaz shahid
Islamiat:
1.Dogars Islamiat
2.Islamic Studies by Muhammad Rafique
3.sohail bhatti's book for MCQs
Pak Studies:
1.Pakistan Studies for B.A by Dr. Muhammad Sarwar (Ilmi kitab khana)
2.Pakistan Affairs by Imtiaz Shahid
3.MCQs by Imtiaz shahid
General Knowledge:
1.Advance General knowledge MCQs by Imtiaz shahid
2.Some good quality book for Everyday Science
3.News Papers like DAWN +
Answers.com: Wiki Q&A combined with free online dictionary, thesaurus, and encyclopedias
Alongside these books The Juhangir's guide for PCS/PMS also a good one which contains all the material about English , Urdu, Islamiat , Pak Studies and Gen Knowledge
Regards,