You can upload up to 25 MB worth of images to use in emails sent from your VerticalResponse for AppExchange account. To upload images:
Go to the VR Email tab in Salesforce
Click the Media Library link under the Resources and Tools section on the bottom of the page
Click the Add Image link to upload images to your Media Library
Images must be in either .gif or .jpg format and must have a resolution of 72 DPI. You should also verify that the color format is RGB and that there are no spaces in the file name. You may also access the Media Library from within the Wizard, Canvas or Freeform email editors. In any of these editors click on the Image button in the toolbar.