You'll need to include more than a basic level of development and calculation in your spreadsheet. There are lots of free spreadsheets on the web. Most of which are very simple and easy to build. People aren't going to buy a spreadsheet that they can get for free. Take yours to the next level by adding all the value you can imagine. Then research on how you can offer a little bit more on the development and functionality side.
You'll need to develop good marketing material. Things like demo videos, which you can find plenty examples on YouTube, screenshots, and keyword rich descriptive text help people find your spreadsheet and communicate the value that sets yours a level above the rest. Excelville.com actually allows you to upload your spreadsheet with all of this marketing material in an easily searchable and user friendly website.
The mentioned package includes valuable programmed spreadsheets such as the "Income and Residual Tracker" - provides professionals in the entertainment branch with detailed information regular and residual income; "The Biorhythm Plotter" - helps users in planning various events and actions based on Primary and Secondary Biorhythms (the spreadsheet solution allows users to choose the right timing for their actions according to personal intellectual, psychological and physiological factors); "Basic Actor Package" - designed to facilitate the process of calculating expenses.
So you've got what it takes to develop spreadsheets that others would find useful. Now you're thinking about selling your spreadsheets to both help people and generate some additional income using your MS Excel or other spreadsheet development skills. Well, as you know, there are pros and cons to everything you do. Read on to find out what some of them are:
examples of spreadsheet packages
what is spreadsheet in excel
blank spreadsheet templates