The old Westinghouse T&D book, now available from ABB is the standard reference. It is getting a bit dated, ABB really needs to do a new edition, but it is familiar to most utility distribution engineers.
In addition to the ABB T&D book, here's some others:
Westinghouse also printed a reference book on Distribution Systems. It was part of the series that the T&D book referenced above was in. There was supposed to be a Generation book also but the group was disbanded prior to writing it.
Cooper Power Systems, Electrical Distribution - System Protection. This book primarily deals with overcurrent and overvoltage fundamentals, protective equipment and applications. It was published in 1960 and I don't know if it's been updated.
ABB, Hard to Find Information about Distribution Systems. This was published in 1999 and is quick reference on various items.
You could also try some of the technical publishers, like McGraw Hill, Wiley Interscience and IEEE.
Hi LaliGuras, Schneider-electric do have several well written booklets available on some topics, altough not an "all in one" handbook. Available online as free pdf files.
On my browser, this is the link:
I work in the Electric Utility Distribution Area and have all of the books previously mentioned and they are good, but I would highly recommend the Electric Power Distribution Handbook by Tom Short, published by CRC Press. It is at least as good as the old Westinghouse Distribution Systems book, but more update. The book by Tom Short contains just about everything you would ever need to know about distribution systems and well worth the cost.