I didn't get the white, I just got the colours I mentioned. Can you paint Polymer clay?
Are those part of the same question or separate questions? If you're thinking of adding white paint to colored polymer clay, you can do that but it might take a lot since colors overwhelm white pretty quickly (it needs to be white oil paint though, not acrylic, or you could use other white pigments or powders or oil pastel shavings, etc.)... might be enough for a small amount of clay though.
Also, you can paint over baked polymer clay, but most clayers don't do it. If you do though, be sure to degrease the surface with alcohol, etc. first, then use acrylic paints unless you're just doing washes (then you can use small amounts of oils).
I wasn't really aware of Emma's online store (though I certainly know of Emma). Her prices appear to be a bit better than Sue's, but I didn't check details about shipping, etc., and she doesn't carry the mini-blocks. She also doesn't carry Premo... only FimoClassic and FimoSoft in the colored clays.
As for why it's more expensive there than here, I don't know why! The usual price of Premo or one of the Fimos in the US (without a sale) is $2.00-2.50, Kato is cheaper by weight and comes in 3
oz bars, and Sculpey is usually around $2.00. The larger bricks are cheaper by weight than smaller bars of the same color but those generally have to be bought online (they're not all the same
weight though--Fimo's are smaller) and it's almost impossible to get Sculpey III in larger bricks).
(So maybe price is the reason that some UK'ers actually end up ordering from the U.S.)
There are definitely ways to use less polymer clay though, compared to other clays.
If possible, for example, you can use some kind of bakable armature under the clay (permanent or temporary), so that you use the clay only for an outer layer. Also, most people don't make huge things from polymer clay, but some do make things as large as veneers for tables, or large vessels and houses, but again the clay itself is usually thin-ish, and those people can afford a fair amount of clay. Some polymer clays are cheaper by weight too, though some of those are weaker after baking (e.g., many of the flesh-colored clays, and original Sculpey in the box). All scrap clay can be used too... all reds mixed together, e.g., or all colors mixed together for what we call "mud."
Let us know what you do with your new clay!
er clay "encyclopedia" http://glassattic.com/polymer/contents.htm
little bit'o photosharing: http://pg.photos.yahoo.com/ph/dianeatglassattic/my_photos