I used to use a homemade one similar to Kaples (www.kaple.dk) - not sure if the guide is on the site but it\'s deffo on the DVD he produced.
I made mine from an old A4 plastic folder, then placed 2 layers of cotton pads in the bottom. I would then soak this with water and run off SOME of the excess water. Then I layed a layer of thin tracing paper over the top (some people use bread paper or cooking papers or even paper towels).
The advantages of it is paint stays workable for hours (with mine it wasn\'t that long, maybe 30 minutes max but still I could add more water and thin it out again).
Now I use a Mattersons Sta-Wet palette, and quite frankly it rocks. I\'m a new painter and therefore a slow one so I need all the time I can get with paint (and I hate wasting paint!).. also I live in Japan so the heat really dries the paint out fast.
The palette has an air-tight cover so paint stays workable for days... it\'s pretty portable too! Even if it\'s a bit expensive, in the long run you\'d probably save money on paint since you waste a lot less.
Here\'s the one I bought Though I got mine in Japan and not from dickblick

I also bought an extra sponge and some more paper!
and a piccy: