So here's what I've got for you: nine websites that offer high-quality photos and images for your blog. These images do not require attribution and may be used commercially.
Furthermore, browse with caution. If you search "woman" you'll get pictures of everything from nuns to "ladies of dubious reputation." Just a heads up.
Pixabay.com
Commercial Use: Yes
This is my favorite site, mainly because, if you're looking for fantasy or sci-fi images (which are ridiculously hard to find without paying a mint) this has a good selection for a free site.
FreeImages.com
Commercial Use: Yes
You'll be asked to create a free account.
PikWizard.com
Commercial Use: Yes
The website also includes Design Wizard (online graphic design software) so you can edit a picture on the spot to meet your specifications.
PublicDomainPictures.net
Commercial Use: Yes
Some pictures may require model release for photos with people (which shouldn't be hard to get).
FreeRangeStock.com
StockPhotosForFree.com
Commercial Use: Yes
Note: You will have to sign up to gain access to download images. Don't worry--it's free!
StockSnap.io
Commercial Use: Yes
Note: Many of the images have a vintage feel to them. Not all, though, so there's lots of options for everybody.
Pexels.com
FreeDigitalPhotos.net
Attribution: Required for free photos
To download, you'll need to have a free account, check off a box that agrees to the terms of use, and watch a short ad that will give you the code to download the photo. If you don't want to attribute the images or want to purchase larger images (free images are small only), you can purchase them starting at $3. From what I can tell, purchase is not required for commercial use.
Wunderstock.com
Attribution: Not required
I found a few specific images that included a note that you must not use for commercial purposes and must credit the artist/photographer, so although most of the images on the site are public domain, pay attention to any additional notes related to the specific image you're downloading. For example, the knight picture I've included here requires attribution.
Additional considerations (from the website FAQ): What if a photo contains a brand, person or another work of art? There may be situations where a photo contains an identifiable person, another work of art, or a brand logo. You may need additional permission to use these photos, especially for commercial projects.
You should never use photos of identifiable people to endorse a product or service without explicit permission.
Write away, happy bloggers!