Weboword-Vocabulary Visually looks like a great resource for SLPs. I am not at all a fan of SLPs selecting vocabulary to teach in an isolated manner. Where do you start? How are they supposed to learn these words within our limited service delivery models? Sometimes it's the best you can do, but I much favor the "Robust" and contextual vocabulary instruction advanced by Beck, McKeown, and Kucan in the book Bringing Words to Life, and subsequent commercial products such as Scholastic's Text Talk. Some years ago at my school, we implemented this approach thanks to a wonderfully supportive literacy specialist (Deana Lew, a SpeechTechie visitor) and principal. It was great for me, because I knew I had done something to build kids' vocabulary without trying to do so in a futile manner in my once- or twice-a-week sessions. I could then work with the body of vocabulary that was being taught in the classrooms, or the trade books used to introduce them contextually.
Thus ends my vocabulary rant. Back to Weboword. This website features terrific cartoons that illustrate specific vocab words. It would be a great model of visualization strategies for vocabulary studies, if one were to pick a few examples, then have students sketch the vocabulary words they are studying right now.
Again, if you haven't already, I strongly recommend reading Beck, et. al.-- these strategies are now widely embedded in balanced literacy programs. You can read a selection from the book at Google Books.