There are some great sites where you can sell your excess creative work.  From photographs, vectors, illustrations, layered PSD files, tutorials and ebooks - there are sale opportunities for your digital content without you having to worry about applying for 'merchant' status. Each site has a different buyer profile and different royalty structures.  Getting started can be a bit intimidating as most sites require an approval process before you can start selling online.

This is not a recipe for overnight success, but rather an income opportunity that you should commit to over a long period.  It can start off as a source of passive income and eventually become your full time income IF you manage to create a winning recipe.

Oh, and be prepared to get rejections,  I've had one library reject an image that become my best seller on another site.  Each site has it's own culture and they each attract a certain buyer. Find your niche and you could find your sweet spot at the same time.

Here's a short list to get you started:

• Graphic River - Vectors and layered PSD (illustrator and indesign templates)
• Theme Forest - Web templates/Themes. From your PSD files to fully functional sites (HTML/Wordpress ect.)
• Veer - Editable vectors, photographs and JPG illies
• Shutterstock - Editable vectors, photographs and JPG illies
• Dreamstime - Editable vectors, photographs and JPG illies
• Fotolia - Editable vectors, photographs and JPG illies

You also have the option on most sites of going exclusive (selling your digital content only on their site) or being non-exclusive. Choosing either is a bit like making an investment choice - higher risk of success or failure with one portfolio of shares, or a lower risk with multiple portfolios of medium performing shares.  The royalties are always higher with exclusivity and some sites allow you to upload your content as either exclusive or non-exclusive. Other sites allow exclusivity (or non exclusivity) based on the author/username, so ALL your files need to be either exclusive or non exclusive.

One of the trickiest aspects is correcly keywording your file, a well keyworded file means that your image will appear more often in the right buyer searches and will result in more sales.

Click here for an awesome keywording tool from one of the top Microstock photographers.