The W probably indicates the number the caller used is in your contacts as work number. You may see M for mobile and H for home in other cases, depending on what field you have the caller's number entered in your contacts.
On ringtones, do you have the Blackberry Help site mobile.blackberry.com in your bookmarks on the BB browser? Could be called something else on your 7290. Go there and follow links to download what you want that is available for you model. And someone else may post links to hosted pages where you can download, but I don't have any to recommend.
Oh yeah.....Welcome to the group!