add links to zazzle storefront (ros2#1803)

* add links to zazzle storefront

Signed-off-by: Tully Foote <[email protected]>
Co-authored-by: Chris Lalancette <[email protected]>

Author: tfoote

source/Marketing.rst

@@ -11,6 +11,14 @@ graphics, and release images, can be found in the `ROS art
 repository. <https://github.com/ros-infrastructure/artwork>`__ Please refer to
 this repository for ROS art work and our branding guidelines.
 
+Stickers, Posters, and Canvas Prints
+------------------------------------
+
+Open Robotics hosts an online storefront on `Zazzle.com <https://www.zazzle.com/store/openrobotics?rf=238583394320947238>`__ with artwork available in various formats.
+
+* `Posters <https://www.zazzle.com/store/openrobotics/products?dp=0&cg=196892405499231339&rf=238583394320947238>`__ Printed on paper with selectable sizes.
+* `Canvas Prints <https://www.zazzle.com/store/openrobotics/products?dp=0&cg=196964974640243022&rf=238583394320947238>`__ Printed on wrapped canvas with selectable sizes.
+* `Sticker Sheets <https://www.zazzle.com/store/openrobotics/products?dp=0&cg=196936312033387169&rf=238583394320947238>`__ Printed on a sheet, 20 per sheet for the small, 6 per sheet in the large size.
 
 Brochure: Why ROS 2?
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