1. A system for determining a tax deductible value of charitable donations for income tax deduction purposes for one or more tax years, said system comprising: one or more partner servers having at least one data source where items are sold, wherein said partner servers are programmed to electronically capture sales data of items sold at said data source; a system server including a memory for storing said sales data, wherein said system server is programmed to: periodically receive said sales data from said partner server; store said sales data in said memory; identify one or more of said items sold that is similar to a donated item that a user has charitably donated; and calculate a tax deductible valuation for said donated item based on said sales data corresponding to said one or more of said items sold wherein when current tax year sales data are not available, a temporary estimate is calculated for the tax deductible value for said donated item using sales data from a previous tax year, and when the current tax year sales data becomes available, the tax deductible value for said donated item is updated to provide an accurate value.