Sorry for the radio silence. I've been away for a few days and I've not been near a computer to post. I have found lots of new paraben-free products though!
The first is Aveda's invati shampoo. My hair is extremely fine and I get lots of breakage from putting it up all the time and swimming. This shampoo is supposed to revitalise the hair follicles on the scalp making hair thicker and stronger. It's expensive - £21.50 for a bottle - but I've only used it three times and my hair already feels thicker, with more texture. Smells lovely too. I couldn't afford the conditioner or the scalp revitaliser at the mo but I think you'd see great results using all three.