If I understand the question correctly, you're interested in knowing if there is a future in manual software testing, and if so, what's the best way to develop one's expertise. A side question seems to be if you should consider branching out into automation as a way to become more marketable.
I've got some opinions on the topic, but they are more anecdotal then well-researched. I'm not a recruiter, I don't really watch job trends, and I don't really know much about your market in Bangalore. That said, if you're interested in becoming a better tester, here are some resources that I've found useful.
One great place to start is James Bach's presentation on Self-Education for Testers. As you look through the slides, pay special attention to his personal syllabus, his levels of learning, the different ways he can choose to learn something, and the entry points for self-education. This presentation is great not only because it provides some non-traditional ways of learning, but it also shows how multi-disciplined software testing is.
Next, I would recommend spending some time on TestingEducation.org. I cite the Black Box Software Testing courses quite a bit in my SearchSoftwareQuality.com answers, but there is a lot of other great content on the site as well. As you watch the videos and read the papers, take some time to look up the reference material. There is a lot of free high-quality material available online.
There are also some books I would recommend you read. There are hundreds of great books that are relevant to software testing, but I'll limit the list to the books recommended by Cem Kaner, James Bach, and Brett Pettichord in Chapter Two of their book Lessons Learned in Software Testing, titled "Thinking Like a Tester." They recommend:
- Tools of Critical Thinking: Metathoughts for Psychology
- Thinking and Deciding
- The Craft of Research
- Cognition in the Wild
- Theory and Evidence: The Development of Scientific Reasoning
- Proofs and Refutations: The Logic of Mathematical Discovery
- An Introduction to General Systems Thinking
- Discovery of Grounded Theory: Strategies for Qualitative Research
- Basics of Qualitative Research: Techniques and Procedures for Developing Grounded Theory
- Exploratory Data Analysis
- Conjectures and Refutations: The Growth of Scientific Knowledge
- Exploring Requirements: Quality Before Design
- How to Solve It
- Things That Make Us Smart: Defending Human Attributes in the Age of the Machine
- The Social Life of Information
(For full disclosure, I'm the President of the Association for Software Testing and am very involved in the Open Certification project.)
Finally, you mentioned automation as a possible interest. I recommend spending some time learning Watir (Web Application Testing in Ruby). It's a great tool, it's free, the Watir community is a strong community, and they have some good documentation for getting started. Another great reason for learning Watir instead of a vendor tool is that you'll be learning Ruby as well. Those scripting skills will serve you well in all your testing efforts.
This was first published in October 2007