Check out Mobility WOD. Just google it and click on the website. A physical therapist named Kelly Starrett has tons of videos on stretches and exercises for all kinds of ailments. I am sure you can find a bicep tendonitis video. I have used plenty of stretches and exercises on myself and my clients with great results. I use to not be able to do dumbell shoulder presses and now can perform clean and jerks and snatches with no problem in part thanks to Kelly.