Possible to find and delete all files with a specific file extension?

I moved all my pictures over from my PC to my Mac. Unfortunately in all the folders are hidden files with a .files extension. iPhoto sees these as folders and shows them as separate sets of photos. Is there a way to search all the files in a directory structure for a certain file type and delete them?

There is, but I don't think it'll help in your case because iPhoto is effectively a database. So, if you deleted those they'd still be linked in iPhoto.. which can cause havoc. There's probably some way to strip these out of iPhoto (and delete them in the process), but since I don't use that software.. not a clue here.

I still have all the files in the original folder, so I can just delete the iPhoto database and import them again.

Ok, so then there are two ways to do this. You can open up a finder window, click on your home directory and in the top right corner click in the field and type .files

Then when it shows all those, hit cmd-a and then cmd-del. Which is probably the easiest. The other method would involve the command line, this is the method I'd use.. but that's because I'm more comfortable with a command prompt than I am the GUI.