If I were advising someone forming a start-up, or forming a start-up myself, I'd want to learn a few things first, and then be able to consult certain experts as I continued.
I would learn from this list of books here, in a page created by Steve Blank. Note Kent Beck's Extreme Programming Explained is listed near the top of this list of books, along with The Lean Startup by Eric Ries, and The Startup Owners Manual by Steve Blank. The list of books is quite long, so I'd get summaries of these books and skim through the few I'd buy, digging deeper as needed. Reading them all would take a long time.
I would consult with Esther Derby for team-work and process improvement. And her books:
- Behind Closed Doors: Secrets of Great Management by Rothman and Derby, and
- Agile Retrospectives: Making Good Teams Great by Derby and Larsen.
I would consult with Johanna Rothman for management and hiring. And her books:
- Hiring Geeks That Fit,
- Hiring The Best Knowledge Workers, Techies and Nerds, and
- Manage It!: Your Guide to Modern, Pragmatic Project Management.
There are a variety of legal issues when starting a business. Nolo Press has a lot of advice. I'd get something like The Small Business Start-Up Kit: A Step-by-Step Legal Guide.