There is an area designed just for this.  It is located here for the E-Commerce Module:

YourDomain.com > Modules > Ecommerce: Products (mX) > Notifications

and here for the AD Module:

YourDomain.com > Modules > Ad: Ads (mX) > Notifications

Enabling this feature will send an automated email to all of the members in the Membership Module associated with your AD or E-Commerce module (whichever you are setting up) with the exception of those "opted out".

You can customize how the email will appear in this area.

There is a "header" & "Footer" area.  This will allow you to have the same header and footer regardless of what items are included in the message.

See an example of a header here:

You can see the header here with the logo, and other info.  That information will get sent every time.  The products in the list will change.  (the notification will include only newly added items)

Now on the Bottom here are the links that are the footer.  This area will be included in every message sent out as well.

There are some settings here for the E-Commerce module that allow you to choose:

"Send Notifications on New Products" will enable this feature.
"Periodicity". - this determines how frequent your message will go out.

"Included Categories". - this allows you to select the categories of products included in your "new items" notification.

You can also choose to ignore a specific "product type."

see screenshot:

For the AD module the "General Settings" area looks like this:

Choosing "Send Notifications on New Items" will enable this feature on your AD module.

Periodicity - is how often this notice will go out.

"Included Categories". - this allows you to select the categories of ADs included in your "new items" notification.

"Only in Customer's Region" - will narrow down ADs that are close to the customer.  The next two fields help dermine what the "region" is.

"Zip code Field" - this allows you to choose a field that you have that tells the system what the Zip code field is.

"Max Distance" - Determines how far away to include in the customers "region".

You can adjust the layout of your Products/ADs Notification and what all is included in this email.  

See screenshot:

"Product List Page for Category Links" tells the system where to send users that click on a Category link from the notification.

"Product Detail Page" - This tells the system what page you want to use as the product details page, when user clicks on a specific product from the notification.

"Number of Columns" - Will determine how many columns of products are shown in your notification

"Row Separator" - adds a line in between Rows to distinguish between products

"Column Separator" - adds a line in between columns to distinguish between products

"Max number of Products" - This determines how many products will be included in your email.

Clicking the "Customize Product List Layout" button will open up a window that allows you to customize your layout, similar to the layout builder found on your product pages.

You can Choose the Fields that you wish to display, and how much room you would like them to take up.

When you click on "Test Notification" it will send a copy of this notification to the email address specified in the "my Profile" area.

And you can also post to FaceBook.  It will post a notice on your Wall that is setup in the "Social Media Integration" area.

For more information feel free to visit Tech Support.