Not every town/city has those Govt run youth hostels and even though some has they are usually full when you visit (esp. in large cities and popular tourist locations).In fact some cities have "private" hostels which are extremely expansive from a youth hostel price point.
Also those railway station dorms are also not at every station and even when they are they are really few.
So how should one (try to find) approach cheap/affordable (but clean and safe) accommodation across Indian towns and cities in general?
I have found the best accommodation without a doubt in India to be Zostel. It's a new concept in India cultivating an incredible safe haven for backpackers, very reasonably priced, incredibly clean and safe. They are expanding rapidly, you'll love them.
The only trusted and real info on cheaper accommodation in India can be gathered from Tripadvisor.in
As most of the reviews here are written by the users and not from the hotel owners or the sites which sell hotels on their websites.
You can also check for hotels who have won the "center of excellence" award as these people know how to welcome guests and one trick you can use is by asking an extra discount from these accommodations in return on a nice 5 star review.
I always do the same and 8 out of 10 times I either get an extra meal or discount.
Just straight on the face, give me extra discount and get a 5 star review. And if 2 people are in a room then 2 reviews and Baam..... discount is yours to be taken...
Hope I could assist,
Pratap from ChetraVouages.in