I just use some plain old tubing I got at the DIY shop for peanuts. Here's an easy "how-to" taken from brewuk.co.uk
1. Place you beer on a table or kitchen work surface and the clean fermenting bin on the floor.
2. Fill a plastic syphon tube completely with water (no bubbles) and cover both end with your thumbs. (Wash your hands prior to this to ensure good hygiene).
3. Quickly place one end of the syphon tube into the beer and then slowly lower the other end into the bottom of clean fermenting bin. Remove your thumb and let the liquid transfer.
4. Ensure that the ends of the syphon remain under the surface of the liquid at all times but be careful not to disturb the yeast sediment when you get near the bottom. If you carefully tip the beer at the end it enables you to get more of the liquid out without transferring the sediment. Don't worry if a bit goes in, your beer will be fine.