Whilst I'm terribly sad that you're not interested in keeping your iToysoldiers account live there is a mechanism in place to cancel your account. Visit http://itoysoldiers.com/user/edit. At the bottom of the screen is a button labeled, "Cancel Account". Click that. You'll be asked for confirmation and then your account will be closed.
If you have a moment, could you drop me a line at firstname.lastname@example.org and let me know what's driving your request to cancel your account? Could I have done something better? Is there something missing? I aim to please and knowing your thoughts on this will help me tons.