What is the Value of Silver Dollars and Other Junk Silver

As an avid collector of silver coins I find lots of friends offering me their old collections of silver dollars, kennedy half dollars roosevelt dimes and so on. While these are great coins to have (and a highly recommended hedge against financial crisis). It is pretty hard to work out the value of individual coins as they all have such weird amounts of silver in them. Amongst the many scrap gold calculators out there I found www.in-gold-we-trust.info to be the best. It calculates the current price of my coins and has the silver content and current silver price programmed into it . I was also able to log on and create a portfolio of all my coins. There are many out there to choose from.