I’ve always been slightly bemused at the concept of hidden files. It’s a bit like making your desk slightly less messy by making some of the mess on it invisible.
Windows has an option in Explorer to show or hide hidden files. Easy.
Mac OS X not so much.
1. open a terminal
2. defaults write com.apple.finder AppleShowAllFiles -boolean true
3. killall Finder
There, all better now.
To switch back to hiding hidden files, repeat with the the boolean set to false.