Depending on your budget there are a lot of different places that you can buy skiing clothes for women from, but these are some of the best.
Onebelowzero.com is a retailer of premium ski gear, including trousers, jackets, base layers and accessories, as well as actual skis, snowboards, and other pieces of equipment. They have a huge selection, spanning hundreds of jackets and accessories and around 50 different types of ski trousers. Their prices are high, with for example one of their top end jackets, the Spyder Women's Chimborazo, costing £899.99, but wear one of these and you'll be the envy of everyone else on the mountain, with its chic and elegant Italian design matched with all the features that you'd expect from an expensive ski jacket.
On the other end of the pricing spectrum skiwear2go.co.uk stocks loads of big brand products at discount prices. For a mix of form and function they've got all the skiing clothes for women you'll need, and while none of them are quite as eye catching as the offerings from onebelowzero.com, they also don't carry the same hefty price tags, and you could get an entire perfectly good ski outfit from them for under £100. They also offer free delivery on everything, netting you an even bigger saving.
If you'd like something more mid range, that focuses on style while still packing in modern ski wear technology, but can't quite stretch to the £500 or more that many things on onebelowzero.com cost, then consider twoseasons.co.uk, their jackets cost on average around £125, while their trousers can be bought for around £100, and hats, gloves and accessories are all substantially cheaper. They stock the latest ranges, and many of their clothes are quite stylish, indeed many of their ski jackets could double as a normal winter coat without looking out of place.