Thanks to Anna from Alchemy of Art, I found a free application to create mosaic photos. It's really easy at a website called bighugelabs.com/mosaic.php and I was able to create this in just a few minutes with my flickr account. I'm using flickr for my photo course and it's pretty easy to use as well.
In doing this I see that it does take some skill to select photos that work together, depending on the light and dark areas and the direction the flowers are facing. This was my third try. I'm going to do some more of these in the upcoming days. (The learning never ends!)
And if you like nature photographs, check out Anna's blog. It's very inspiring.
Thanks so much for your suggestions Anna.