Contact Trulia to remove your account as they are the only means to have it deleted.
Click on your name in the upper right corner. A drop down menu will appear that includes a tab labeled "help".
Click on it and then a tab will appear next to your name that says "contact us". A new window will appear for you to send Trulia an e-mail message requesting to cancel your account.
Hope that helps.
Prudential Connecticut Realty