There are genuine websites that you can sign up to for free product testing or (and my favourite) for Mystery Shoppers. Some of the links below may be my personal referral links from the websites (I will mark these with *), but you can always go via the website direct. But most importantly, none of the websites I belong to would send a cold, blanket email to you asking to join them.
So first up, Product Testing
BZZ Agent is a site where you complete various surveys and based on your answers, you will then be matched with new products and services (usually free) to try. You are then asked to complete tasks based on your opinions of these products. You do not have to have Twitter, Facebook or a Blog, you can complete your tasks direct on their website.
There may be occasions that you are only offered a discounted price to try a product, but you can always decline these with no effect on your score. Depending on the product you will either receive the product direct or vouchers to purchase the product.
Click Research have products to review with a slight difference, the products you receive will be in a plain bottle/tube etc so you will not know what brand the product is - which is a great way for you to be completely unbiased.
When you register for this site you will have a lot of surveys to complete. These are actually called Profiling on this website and this detail is needed to make sure you get the right products to review. I have recommended this site to a couple of people at work, who only completed a couple of surveys and gave up - if this is you, this is not the website for you.
Tesco will send you vouchers to purchase your review item, you will also receive additional money off vouchers to pass on to friends and family.
Home Panel. The Home Panel is a website for customers to give their feedback to Tesco on the quality of the products Tesco sell. This is completed on the website direct.
Since writing this post last year I have been working with another website called I love to Review. This is a site that once you register your details you are sent an email with details of up and coming items to review. If any products fit your lifestyle you click on the 'apply' button and you are then sent a code to purchase the item from Amazon. All reviews are completed on Amazon, and if you have Prime, you won't need to pay for postage.
There may be other websites out there, but those listed above are the ones I know and use. I am not inundated with products to review but every now and then one of the above will send an email out asking to apply for a new product to review. It is a controlled email, you have to log into your account to apply. It is not a generic email from some strange account asking you to 'press this link' to apply.
I hope the above has helped and do let me know if you'll be signing up with any of them, after all, who better to test and review products then the end consumer?
Due to the length of this post, I will post the Mystery Shopper links on a new blog.