Hi Lorraine - you're going to need storage space such as an external drive. maplins do one on special offer at the moment, a maxter for around £100 and its 750gb (thats a lot of space and i'm saving up for one.... its also a good idea to keep them on an external drive in case your computer has a fatal crash)..
the way i do it (i'm sure there are simpler ways) is to keep all raw files in date form (you can come back to them whenever you want, edit them or bin them); then i have a folder for edited images which are saved as tiff (large file, not resized, in case if ever want to print them); then lastly a folder for resized images saved as jpeg for the web. so thats 3 separate files of shots i want to keep.
wonder how other filing systems work?