No way do you stand to lose your money over this.
Under the Distance Selling Regulations if goods are not received within 30 days of ordering you are entitled to a full refund. There are some exceptions to this but I'm assuming you are a consumer purchasing an off-the-shelf item.
I would suggest you cancel the order in writing (e-mail will do) with the supplier and ask for a full refund. As peanut says, you can also involve your credit card company if necessary.
If the goods magically arrive after you have cancelled your order you aren't obliged to keep them, you have a 7-day cooling off period which entitles you to still cancel your order and request a refund. You must not use the goods though, they don't have to accept them back if you do.
Do a search on Google using the term ' distance selling regulations uk ' and you will get loads of useful info back.