fragrancedirect.co.uk is good (I've used it myself to get hold of the ocassional hard-to-find smelly) and Boots.com sometimes has good special offers. Amazon is also good for picking up the odd bargain. Stick with reputable dealers like these and you're guaranteed to get the real thing. For niche brands, and those like Creed who don't really like being sold online, have a look at www.lessenteurs.com