use Universal Email for this.
create a page with a form on it. the form will only need to have one input box for you to enter the email address you want to send the message to, and a submit button.
Then apply universal email (WebAssist -> Create Email Message). For the from address, enter your email address. for the To address, click the lightning bolt icon and select the email address form element.
for the body, make sure the Create File For the Email option is _not_ checked. Then click the DW Edit button, and design the email body using Dreamweaver.
