I've enjoyed having an O'Reilly Safari subscription for random access to books. In particular, the Pragmatic Programmer and Designing Data-Intensive Applications.
I've also had good experiences with SCPD courses from Stanford, if your budget would cover those (they are at the other end of the price spectrum).
For anyone in India, the cheapest way to get a Safari Books subscription is via an ACM Professional or Student membership. It’s only INR 1500 per year.
I frequently muse about whether Safari, which is valuable, is worth the $399/y
Pro: I like being able to sample the same topic from many prospectives (one chapter from each of 3-5 books)
Cons: I wouldn't spend /that/ much on books in a year, the quality of the videos is widely variable, the search (including quality filtering) is _terrible_, and the inability to bookmark specific talks within a conference is infuriating. Part of the pain is how close it is to being really good!
To be honest, I didn't realize it was that expensive for an individual (we might have some sort of team pricing -- I'm not sure what my seat cost but I assumed it was cheaper than that). At that rate, you're probably better off with a $400/y budget for paper O'Reilly books.
That said, it is fun to be able to randomly access books on a topic without having to decide whether or not to buy them.
I've also had good experiences with SCPD courses from Stanford, if your budget would cover those (they are at the other end of the price spectrum).