I am in the process of building a spreadsheet that I believe I could sell. I was wondering about creating a website to sell it from and looking around I see price estimates from $100 a year to thousands of dollars per year. What I would require is a site that will allow for instant download after payment, an email address to go with it, and hosting of a few videos and articles. Security would be important, I wouldn't want a website that easily allows one to steal my customers' credit card info. How much would it cost for something like this a year? I had someone quote me about 20% per transaction to host it on their site but would prefer to keep it completely under my own control.

Should be under $100/year.  GoDaddy's pretty reasonable, but there are horror stories about leaving them.  I'm w/ GoDaddy, but I've not set up an online store yet.

Hello neighbor, congratulations on having a product to market. To address your concerns, it's very common to have a transaction cost for any type of payment processing (20% is high, obligatory bitcoin option mention here), and for security reasons as you mention, you're unlikely to be hosting any of that yourself (don't invite the PCI into your life).

That said, my first mention would be SquareSpace, that will have all your needs in one place (hosting, domain, email, mature commerce).

If you find a better platform or want to do more of it yourself, I'd mention Gumroad for handling the purchase/payment process. With this option you'd create your landing page with the videos, articles, and sales copy. Gumroad would just be an embed into the page or a click away for customers.

Good luck to you.

SquareSpace is a great option.