Hi,

You can get pdf version or e book for  any book which are given by PSEB on it's official site itself. It's official site consists of all the books related to all the subjects and streams. You can also find books for other classes too. Here is a link where you can get all the books : http://www.pseb.ac.in/ebooks#

You will have to copy this link in the browser so as to get your required book.

I hope this helped you.