Tell-a-Friend is to be used for recommending to people you know. You should only contact people via email or other electronic communications if you have their consent.
To get their reward, your friends need to click on the "Been referred by a friend?" link at the checkout and simply enter your name [Sarah Cattermole]. If there is another person registered with the same name, your friends will be asked for your email address.
Sell some of your old junk for free via Vintage Cash Cow. They send you a box to fill and send back (free postage), value your goods and give you a valuation. If you accept, they pay the money directly to you, and if you decline then they will send your items back, free of charge.