Mac Mail Send Only / Send As

Is there a way to set up e-mail accounts in my Mac mail that allow me to "send only" from them? For example, I have a couple e-mail accounts that I only use for commercial / e-commerce communication (airline tickets, eBay transactions, etc), but am otherwise not interested in setting up as an inbox because they simply flood with spam.

Is there a way to set up Mail so that I can choose to send a message as me@xxxxx.com (rather than me@mac.com); WITHOUT adding an inbox for this account?

thanks!
Mark