First of all watercolour palettes come in various shapes and sizes from small to (very) large. If you are painting on say half sheets or larger and use big brushes size 16 and above and large flats, 1" or more, then it is obvious you need a big palette. Not everyone uses conventional palettes and various sorts of flat trays are used by artists, including some top professionals. Butcher's metal trays of different sizes and/or the flat plastic ones sold in some kitchen shops can be perfectly adequate. With such trays you squeeze out paint from tubes. This method is normally associated with limited palettes of 6 to 9 colours. You can mix large quantities of paint but it can be wasteful with what remains and is then washed off.
The above selection of palettes includes two of the largest, the John Pike (A) which is on the left hand side complete with lid, which can also be used as another mixing area. The Robert Wade Palette (B) is at middle bottom with the lid, also used for mixing, touching to the left. Top centre is a muffin tray (E) (as used by the artist Trevor Waugh) and to the left (D) is a plastic palette of a type commonly available. Centre is the Zoltan Szabo palette (C). The three remaining palettes in the top left hand position are top a cheap aluminium version (F) commonly available and underneath the smallest palette, a Windsor and Newton plastic one (G) with an empty metal palette (H) of the sort commonly available but in this instance filled with empty full pans. I have labelled each palette with a letter A to H, but you may need to click on the photo and enlarge it to see the letters clearly.
What you need and what you should obtain depends on how you paint and whether you use tubes or half/full pans. The other criteria is how large you paint because in my experience most amateurs paint fairly small. These are only a selection of palettes that come in four basic materials, plastic, metal, ceramic and porcelain. There are other sorts but not usually used for watercolours. The John Pike palette is American and all the information you need is here http://www.johnpikeartproducts.com/. The Robert Wade palette is obtainable in the UK from www.apvfilms.com/ . The JP palette is very popular with professionals like Mel Stabin www.melstabin.com/ and in his book `Watercolor, Simple, Fast and Focussed' is illustrated more than once as he uses it for everything including his plein air painting! I'm not sure about the Zoltan Szabo palette as he is deceased (as is John Pike) but it is probably still available if you Google it. Added Note: Yes it is. Try www.ZoltanSzabo.com/ Wade and Szabo palettes are vacuum formed whereas the Pike palette, those from Herrings and several others are made from much stronger materials.
What is readily available? In the UK we have Ken Bromley, Jacksons, Lawrence, Herrings and several others possible suppliers. Great Art are German but have a UK telephone ordering number. Great Art have palettes from 85p up to a `professional' box with 48 large wells (!) costing £133.40p. Try Great Art http://www.greatart.co.uk/ . The enormous catalogue stretches to nearly 400 pages. Jacksons, who tend to be the most popular supplier amongst my artists group http://www.jacksonsart.co.uk/ list a large number and have recently added the superior and more expensive Holbein metal palettes. They are not yet in the catalogue but are on the website. Bromley http://www.artsupplies.co.uk/ also list a good number including the plastic Maxwell palette `designed by artists'. Herrings are interesting because the Herring brothers (and family) are enthusiastic artists and have introduced a range of artists products `designed by artists for artists'. These include several palettes plus other items like easels. Herrings also sell two `professional' metal empty boxes. Herrings have a website http://www.frankherringandsons.com/ but it is still under construction and art materials are not yet on it. Most of the above also sell various empty, lightweight, metal boxes, cheaper and not to be compared with the more expensive heavy duty `professional' sorts.
Here are three typical metal boxes, purchased empty and filled with a mixture of half and full pans. I suggest half pans for the least popular colours and full pans for the colours you use most often. You can purchase empty full and half pans at both Jacksons and Bromley and some of the others and fill them from tubes or half and full pans from manufacturers like Windsor and Newton. Not every paint manufacturer offers both half and full pans. One of my local art shops in Bath (Minerva) also sells them in packets of ten. You may note two of the boxes above have the Scminke Logo. Some of these boxes, very similar whatever the source, have logos like Scminke, Rembrandt and Lukas. others nothing. They are basically cheap enamelled metal so don't compare them with the more expensive heavy duty palettes I shall cover in Part Two. They do the job if price is an issue but won't last more than two or three years with heavy usage.