If you're budget-restricted, your best bet is this Susina Turtleneck. It's a wonderful product, while not very pricey. Another strong contender for your wardrobe is this Rollneck. While the price of this item is rather reasonable, it will surely attract a lot of attention. You may also want to look at this Turtleneck. This item is not expensive either, but it will make a difference in your wardrobe.
If you're a bargain shopper, look no further than this Love Moschino Rollneck. This item doesn't cost too much, but absolutely deserves a spot in your wardrobe.