There are a number of thyroid supplements on the market, like Thyro-sense, that you can get from most Health Food stores, check with your doctor first though.
Also, there is a supplement called L-Tyrosine, google search "L-Tyrosine + Thyroid" for more information. L-Tyrosine is a common ingredient in a variety of thyroid health supplements.
I was reading yesterday that Extra-virgin Coconut Oil was supposed to be the latest and greatest for thyroid health... not sure how valid that claim is however.