You answered your own question when you said "I built it for me, but feel that it has commercial viability for many others."

Other than what you said, what problem did you design it to solve? Who are "many others"? What problem do they have?

Why not cruise the Excel forums on the MS support site and see if others have that problem? Enlist some of them to help you find how to market it?

Hi:
Taking a spin through the website your product does appear to have some promise. But then again, I'm not your target market.
Before you pull someone in to help you with this, you need to do some legwork:
* Who do you envision your ideal customer to be? Where do they work? What role do they have? What headaches do they have? How do they currently do the job that your product handles?
* Then connect with some of those ideal customers. Face to face is best. Don't ask them about your solution, but ask them how they do their jobs. What headaches do they have? How do they navigate different data buckets when working with Excel? How would they envision a solution?
* Compare your findings to what your product does.
* Complete the Business Model Canvas (https://www.strategyzer.com/canvas/business-model-canvas) to get a great handle on how your business might work.
Once you've completed these steps, you'll have much more of an idea on how your product might fit in the marketplace.
And once you bring someone in to help you, you'll have a much better story to tell about your company and its product's potential.
If you wish to discuss, send me a PM through Clarity for 15 free minutes.
Cheers,
Kerby

Hi, I hope you are doing great!

To answer your specific question on how you can find someone to help you, I would definitely use Clarity.fm (you are already at a good start, just change the perspective of the question) you can also look into LinkedIn or Upwork.

Those are the 3 places where I would start... and you might want to frame your question different, something along the lines of...
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Are you a specialist on finding markets? Are you a Business Developer? If so, we need to talk...

I created a solution for a common need programmers and Excel users have, if you have expertise in the industry please send me a message so we can talk further...
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But please, please don;t try to do it yourself, I've seen many great products that have a lot of potential but have failed because creators don't approach professionals on the field they need help with.

The best of luck on your endeavor

Gabriel

The target customer is the person who eventually decides whether to use your product or not. Market segmentation will help you define your “buyer personas” and describe them to your product team so that everyone understands who you are building the product for. It’s important to find specific needs that can create an excellent market opportunity. The market might be full of similar product makers. When road mapping your product processes, make sure to include new features, fresh new ideas, and stuff that can excite buyers.
You can read more here: https://uxplanet.org/understanding-product-market-fit-from-start-to-finish-596a4653814
Besides if you do have any questions give me a call: https://clarity.fm/joy-brotonath