Free Option Pricing Spreadsheet
Download the zipped version Option Trading Workbook (53 KB)
Download the Excel file Option Trading Workbook.xls (259 KB)
The above option pricing spreadsheet will allow you to price European call and put options. You can also enter up to ten different option/stock leg combinations to view the expected payoff at expiration.
Alternatively, you can visit the online version of these calculations at Option-Price.com
The option strategy graphs provided in the spreadsheet are only 2 dimensional, however, if you would like something a little more advanced when it comes to payoff profiles then I recommend Voptions. They have an outstanding piece of software that calculates 3 dimensional graphs for various strategies - with a free trial too.
Download the free trial of the Visual Options Analyzer.
Just to note that much of what I have learnt that made this spreadsheet possible was taken from the highly acclaimed book on financial modeling by Simon Benninga - Financial Modeling - 2nd Edition
If you're an Excel junkie, you'll love this book - Simon's a freak. There are loads of real world problems that Simon solves using Excel. The book also comes with a disk that contains all the exercises Simon illustrates. You can find a copy of Financial Modeling at Amazon of course.