Performers - Other clarinettists on the web include Emma Johnson and Michael Collins (both previous winners of the Young Musician of the Year) and the Arundo Quartet, whose members include one of my former teachers, Jill Sadler. Listening to other clarinettists in action is a great way of seeing how it's done, and can be a real inspiration to do more practice!
Manufacturers - Hanson, Buffet, Yamaha, Selmer, Peter Eaton (whose website also has excellent advice on clarinet care), and for reeds, Vandoren.
Retailers - For any musical purchase, it's often easiest to start at your local music store - The Music Shop in Merstham is my local shop. If your local shop can't help, visit Howarths in London (near Baker Street tube), or for reeds, try Reeds Direct.
Exams - The best-known music exams board in the UK (and quite possibly the world) is the Associated Board of the Royal Schools of Music. Exams are also offered by Trinity College and London College of Music.
Repairer - No matter how much care you take of your clarinet, it may need a repair or overhaul from time to time. My nearest repair centre is Woodwind and Brass repairs in Horley.
Personal favourites - See some more of my hard work on the Reigate and Redhill Choral Society website, or escape from it all at the Bluebell Railway.