Project for informational products

Basically I have an ebook, but I decided I'd want to sell something else to go along with it so that it would be a more attractive product.? The ebook is not the problem, but what I need is some downloadable software to offer the customer, so that they can plug in numbers and have the answers very easy, at the tip of their fingers.? There are formulas that I know that you can use to create some software that can be downloaded at the time the ebook is downloaded, as a part of an entire package.? ? For example, there is a formula for BMI (body mass index) for fitness and you plug ina? couple numbers times another number and you come out with a certain number, but there are different variations.? I would like a program that they could download where they could do something similar, as well as plug in the number of the amount of calories they want to eat per day, and have the program break down the carbohydrate, fat, and protein content of every meal.? There are formulas for all of this, and all the data I already have, we would just have to be able to talk to each other alot with this project, because it is going to take communication to get it done.? Let me know if you can help me with this and make some attractive programs for my ebook customers, or my paying membership site customers ## Deliverables I just want to mention that I chose website and desktop software because I am not sure yet what I want created.? This software would be good if my customers could download it from my website, but it would also be okay if they could go to a member's area within the website to use the software, I haven't decided yet, so keep that in mind.? I may offer a few different packages that's why I"m saying this.? One member may pay monthly for a membership and therefore have to log on to use the software, while another may choose to only purchase the ebook and software, not the total package, so that's something to think about