TortoiseSVN The coolest Interface to (Sub)Version Control

If you haven't committed your changes yet, you can do a revert on the parent folder where you deleted the file or directory.

If you have already committed the deleted file, then you can use the repository browser, change to the revision where the file still existed and then use the command Copy to... from the context menu. Enter the path to your working copy as the target and the deleted file will be copied from the repository to your working copy.

You can also restore a deleted directory using this technique.

If, after the file / folder has been restored using this trick, the log dialog doesn't show you the history of that file, don't worry. The history is still there.

If you copy a file in SVN you copy its history too. But the default setting in TSVN's ShowLog is to 'Stop on copy', which means that when you look at the history, it only goes back to the branch point. The reason for this is that when you are looking at a real branch of a project, mostly you only want to see the history of that branch. To see the whole history in ShowLog you need to unselect the 'Stop on copy' checkbox and click on 'Get All'.