First up is Elomi, from lingerie giants Eveden. This ranges combines the best bits of both of Eveden's other big players; Fantasie’s tactile fabrics and subtle details, and Freya’s knowledge of how to craft a bra that offers support without being frumpy. The Paloma set is, to me, the perfect V-day pick because it’s not red, black or covered in hearts, but its still got a bit of subtle sex appeal. It's available in sizes 36D - 42G and it's currently in the sale. The bra is £20 and the briefs are £5 at Ample Bosom. If you can't find your size in both pieces, try ebay - I've made some really bargainous matching sets this way!
Obviously, the right lingerie starts with fit, and for that you need an understanding of how a good bra should fit your body. The old 'measure under your boobs and add four inches' method is outdated and can be particularly unreliable on plus size women. I'll defer, at this point, to two ladies who explain it far better than I ever could: Georgina of Fuller Figure Fuller Bust and Cheryl of Invest in Your Chest. Consider them your bra gurus from now on.