Those lower body stretches in the running article should help with cycling, too. But if you do long rides, you may also need to give some extra attention to stretching the low back area and hips--tightness there can cause pain/fatigue in the legs--and any other problem spots you experience, like upper back/neck, or even feet and hands. One thing that's helped me add time and distance to my cycling has been doing regular yoga poses--especially those in the Sun Salutation: yoga.about.com/od/yogasequences/ss/sunsalu
I also tend to have tightness or soreness in my illio-tibial band (along the outside of my thighs/hips) after long rides, and I use a technique called "self-myofacial release" to deal with that problem. You can google that term for details and photos, but basically it involves applying pressure to sore spots, by laying on a foam roller (or tennis ball, etc) until the tightness releases (it's not much fun, but it works :). Also, self-massaging tight areas can help a lot.
Hope this helps.