I'm a fan of MS Excel _ my apologies for those who have issues with Microsoft _ because I find its powerful calculations are easy to manipulate to help me better understand my finances. It doesn't really matter though which spreadsheeting package you use so long as you are able to calculate your amounts effectively. There are commercial budgeting worksheets available but if you want to create your own its a simple process.
An average wedding will spend 50% of their budget on the reception. This includes food, drinks, and venue. 10% of the budget is spent on the attire. This includes bridesmaid dresses, suites for the groomsmen, as well as the bridal gown. Another 10% is spent on the decorations, and another 10% on music. Plan to spend another 10% on a photographer or a videographer, and the rest for miscellaneous charges. This of course is not set in stone. Your wedding might be much different then this. But when setting up your wedding budget worksheet this is a good place to start.