Hemerocallis - (Daylilies)
The British Hosta & Hemerocallis Society - Your first stop with many other useful links
A la Carte Daylilies - Lovely couple - Jan & Andy who started it all off for me - huge selection
http://www.eurocallis.com - Francois, now in Spain. Here you can spend a shocking amount on the newest American introductions. Very reasonably priced older varieties also on offer and Francois is the best at getting that certain plant for you.
Eddington House - The nursery to visit on the Isle of Wight
Ben's Botanics - informative and passionate
Jearrards's Herbal - so much useful information on many species
Woottens of Wenhaston - first stop for species pelargoniums and so much more.
http://www.autumnasters.co.uk - Old Court Nurseries - specialising in Asters - brilliant late summer, perfect for extending the season.
http://www.callygardens.co.uk/ - Cally Gardens - deservedly well known - some choice plants.
http://www.littlebrookfuchsias.co.uk/ - great selection of very well priced fuchsias including many Encliandras.