You can get lots and lots of things for free, but be warned, use a separate email address or you'll be bombarded with spam.
Via Supersavvyme I've had hundreds of pounds worth of product tests and free gifts, also certain survey sites have product tests so you might get to test a mid price facecream and get paid £15 for your thoughts on it.
Some of the women's magazines run test panels so if interested take a look.
Often there are coupons available but the product will still work out more expensive than an own label version.
Iceland is brilliant for freebies, this week you get a free pack of Magnums if you buy 2 barbecue packs. They always have promotions like this.
It takes a while to learn the ropes of how to try things and get them cheaper but after a while it becomes second nature.
Try the student money saving sites, they are an excellent source of tips and tricks - not just for students, and magicfreebies is a good one.