At the moment I upload smallish watermarked images into a password protected gallery on my blog. Clients email (or call, but so far I've only recieved emails) the print number and size and I post them to the client.

I order my photos through a lab in Melbourne so they are delivered to me in nice stiff cardboard and then in a flat box. I pretty much re-use that same cardboard once I have checked the prints and trimmed them (they have my business details at the bottom which needs to be trimmed off), and then I pop that into a toughbag. Oh... and the prints are in a plastic sleeve before they are pit between the cardboard too.
I'm happy to deliver in person for locals, or they can collect.

I am setting up Photocart over te next month though so that will make ordering even easier for my clients.

If I come across someone who does not have access to view my website (doubt that!!) but if I do, I'm happy to do a slideshow of the images on my computer, or I can post a watermakred set to them on disk.