Alison, have a look at some of the tool suppliers with links on here, such as Arc Euro Trade, Warco, Etc. Items on their websites should help you identify all or most of your dads equipment and give you the cost of such items when new. Setting a price for your items will depend on condition, but once you know what they are Ebay should give you a fair idea of how to price them up. A great place to sell them would be the Homeworkshop site. I don't know how to post a link to that site, but I am sure someone on here could help with that. Sorry to hear of your loss, and good luck with clearing the tools.
Dek.