You're probably thinking of simply flexible PVC pipe (hence why it can be cemented into fittings like normal ridgid pipe). It may have trade names but any decent irrigation supply place should carry it. I've done a few orders with these guys online
http://flexpvc.com/ who do carry it and tons of fittings to go with. I've also gotten some PVC fittings and pipe from Corix Water Products in Surrey. If you get desperate you can give them a call but I think they're some distance from you. I'm sure a quick search in superpages and a couple phone calls should get you in touch with a closer reseller.