Be careful...
You'll find numerous threads on here of auto-blogs leeching images from other people's sites and getting a rather nasty letter from a pee'd off IPR lawyer who won't take "I'm sorry - I didn't know..." for an answer...
DO NOT use other sites copyright images. Get on to some free image sites (and make sure you understand the difference between royalty-free and plain 'free') and use some image integration/posting software/plugins working randomly from a pile of images that you upload to a specific directory.
Eseentially, you can use 'spinning' software to do this as you post, as you just need to spin the URL/location of the images on the local drive inside the HTML img code.
i.e...
<img src="img/{Pic1.gif|Pic2.gif|Pic3.gif|Pic4.gif}" class="YourImageFloatClass" />