I have tested Fugu, which works very well for SFTP access on the mac. Fugu is freely available from the University of Michigan: http://rsug.itd.umich.edu/software/fugu/
I was going to provide screen shots and examples of Filezilla also, however I could not get it to work. It seems to default to FTP protocol -- which is older and insecure. I looked at the options and I do not understand how to change it to use SFTP instead. It is not clear to me at all. The interface also seems a bit more clunky, like "plain X". In contrast, Fugu is very polished and looks like a clean Mac application.
open the preference window and under the "Transfers" tab, make sure it is set to retain file permissions.
Fugu opens and shows you a listing of your directory on the left side of the window. On the right side it prompts you for a destination. Enter sftp.uwo.ca and your username, and public_html for the Directory. Then click the Connect button. Enter your password when prompted.
The right-hand section of the Fugu window will now show your remote directory on the UWO servers. You can navigate your local machine in the left-hand section, and drag and drop files into the remote location on the right. (My screen-capture tool does not grab the mouse pointer, so it is not shown in this image. The purple arrow indicates a file being dragged.)
Your files are now uploaded and (in this instance) you should be able to view your files on the web server. If you get errors when trying to view your files you might have incorrect file permissions. You can use the "Info" button at the top of the fugu window to adjust those on the remote host. Select the file in the right-hand section, and then click the Info button. In the pop-up window, make sure to tick the box that allows "Others" to have read access, and then "Apply".
End of Instructions.
8/Mar/2011 -- Art Mulder