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 templates designed to use for saving calculations varies according to the saving calculations made depending on the types of calculations to be made. These spreadsheets make the calculations and the data entry easier than doing it by any other format.
When VisiCalc hit the scene back in the eighties (in the last century), the relatively small group of Apple II users went crazy. It was like manna from heaven for the poor accountants, scientists and engineers who were used to filling in enormous analysis sheets with a pencil. Now, they could use VisiCalc to do the same task, AND calculate the result automatically.
Once you design the type of budgeting spreadsheets you want to use, it will be easy to copy it for subsequent months or years. You can also use just one sheet and create tabs for each month.
uses of spreadsheet
examples of spreadsheet packages
types of spreadsheet