Visual design is important in building a website. Content matters a whole lot not only to your visitors but also to those wonderful SEO algorithms. Below are some resources for building visual content for your website.
Podcast
https://shows.pippa.io/moderrn/resources-for-building-visual-content-for-your-website
StockSnap.io
A great royalty free website with an impressive collection of photography is StockSnap. However, the drawback in relying on photos from StockSnap is that you begin to notice other sites using the same images that you're also using. Make sure to read the license of the photography you decide to use.
Pixeden
There will come a time when you may not want to use photography for your website or blog. The site Pixeden offers graphics resources from icons to illustrations. Just be aware that similar to StockSnap, many popular images are commonly used among on other websites.
Your Current Photo Library
We live in a day of age where everyone has an impressive camera on their smartphones. You've probably have taken a dozen photos that you could implement for your own site.
Summary: Resources for Building Visual Content for Your Website
In conclusion, there are many great stock art sites to help in building a photo library for your website. These sites are great if you're looking to add visual content to your site or blog. Once you have a starting point you can add in your own photography.