http://quittea.com/buy-quit-tea/free-quit-smoking-aid-sample/ -it’s to help quit smoking. This hasn’t been posted in about a year but it’s still available.
https://secure.nectresse.com/free-sample -the form wasn’t working earlier but it seems to be working better now.
http://www.egotea.com/company/link_rewards.htm -if you post their link on your website you can get free tea. It doesn’t say what type of site it has to be.
http://www.facebook.com/EmergenC#!/EmergenC?sk=app_251260384952259 -this one hasn’t been posted in a while. You might not be able to sign up again if you did before though.