The Prof.Control Edition of LV does come with the whole Enterprise Connectivity Toolkit including the Internet Toolkit. "URL Get HTTP Document.vi" is in the Functions>>Internet Toolkit>>URL Client VI's palette.
Did you install all the toolkits? Does the Internet Toolkit appear in your function palette?
With all the CD's in the Prof Control Edition it's pretty easy to miss one. Toolkits are on the aptly named 'Toolset Software' CD.
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Fading out. " ... J. Arthur Rank on gong."