Where to get these books?

Where can I get the following books:

Sadh Sangat kee Prarthana
Vajibul Arz
Guru Pad Prem Parkaash
Vimal Bibek Varidh Khalsa Shatk


I dont know any of the authors .

I found out that" Sri Guru Pad Prem Parkaash" was written by ex head Granthi Bawa Sumer Singh ( 1930's). Does anyone know about this book.

ALso where can I get a copy of the small book about Raag mala which Bhai Sahib gave Giani Gurdit Singh JI?