Sorry, I was going to ask her this morning, but she's out the door early. I have raided her PC to look at her gardening bookmarks...
She's getting them from
Garden Skill (check the "raised bed" menu on the left). She was using another brand (Linkabord) that's no longer available. You can get kits or just mix and match. They will even make stuff to order. It's pretty easy to use, so as long as you can hammer a peg into a hole, you can put it together. You don't want them more than a meter wide in one direction so that you can reach over them to garden without having to step into them, but you can make them bigger if you want. My wife reckoned she did about four or five beds for the price of one made of sleepers. It's not pretty or rustic, but it's fairly innocuous (no worse than a plastic flower pot), and very easy/cheap to use.
The other advantage is because they are so light and easy to put together, instead of me lugging sleepers about and having to screw them together and waterproof them with plastic, dig up and put them on gravel for drainage etc, the wife just wanted a hammer and she put them together herself.
She put them on some weed suppressor, then filled with with compost/vermiculite (much cheaper from Travis Perkins as a building product).
If you're growing veg, there's some stuff that works better in pots or bags. For instance with potatoes, she's got these tall bags that fold down. As the potatoes grow and you put more soil on them to encourage them to get a taller but grow more potatoes under the ground, she just rolls up the side of the bag and adds more soil, and you end up with a three foot tall bag that's all potatoes. You can even move them around like that.
