What are proven methods for finding ideas that bring value to users?

Understanding pain points (problem) and then talking to them about solving that problem and its worth to them.
Ask them if they can pre-pay (with additional incentive of course).
And then building it rather than trying to build first and then trying to sell it.

Stop thinking in terms of ideas and start thinking in terms of solutions for problems.

So I would rephrase your question to: How do I discover problems worth solving?

This is a much easier question to answer, although it is somewhat personal. Here are the related questions I ask myself:

  • Is this a problem I care about?
  • Is this a problem I have myself? (helps me better understand the nuances of it)
  • How much if any are people currently paying for sub-optimal solutions?
  • Is their any other evidence that shows people are willing to invest in a solution?
  • How many people have this problem?
  • How significant is this problem for them? How often will they encounter it?
  • How much does this problem affect them? How high is it on their priority list?
  • How easily are these people reached?
  • Are people aware of their problem?
  • Do the people experiencing the problem also have the ability to do something about it? (important in B2B)

You can do this research before you write any line of code, but coding a prototype can also be a good way to get answers to these questions. Finding that balance depends on your specific circumstances.

Edit: My questions are more about validating a specific problem, than coming up with problems to solve. To come up with problems you can later verify, there are some suggestions:

  • Look at your own life. Are there things that annoy you or feel inefficient? Those might be problems worth solving.
  • Same for friends and colleagues.
  • Search Twitter for queries like "does anyone know", "why can't", etc. Get creative!
  • Search online discussion forms for problems people need help with.
  • Also look at Quora, WIP Q&A, etc. Questions often arise from problems.
  • Same for books. Look at popular non-fiction books. Which problems do they aim to solve? Could you build a product for it?