Focus less on your own problems and pay attention to the problems that other people have. Especially problems where they've come up with really hacky workarounds -- think Excel spreadsheets, weird approval/email chains, manual import/exporting from one system to another, etc. All good signs that there's something to be improved, and that it's enough of a problem to put effort into.

Couple of other thoughts -- your problems are likely not to be technical. They're going to be obtaining domain knowledge, marketing, and supporting your product.

I'll second the recommendation on "Start Small, Stay Small". Also Eric Reis' "Lean Startup" and 37 Signals "Getting Real". The latter two were really helpful in getting my most successful project out the door and making money.