Pictures are the eye candy of a blog. IMO if you are trying to market a product or service in your blog you've got to have photos. They can easily depict your product if you have a tangible item you produce or set up. For those like DJs it's a bit trickier but showing the emotions of the bride and groom and very often the response of their guests can show the viewer the result of the service you provide.
I purposely chose not to add any additional photos or images to this post just to show you how boring a post with no photos looks.
Where should you get pictures from? Basically there are three choices:
1. Take them yourself
2. Get them from a friend, client or colleague (Give photo credits when appropriate)
3. Copy them from the internet - with permission from the copyright holder. Unless it is marked as such that you are free to use you will most likely infringe on the copyright holders rights without a release or license to copy and use their work.
When adding photos make sure to rename your image file to reflect what your photo does. For instance remove the original file name which is usually something like “P0001973.JPG” and replace with a keyword rich file name like “swarovski_crystal_pineapple_cake_topper.jpg”