I hope you meant "trawling the HP site" rather than "trolling the HP site"!
But back on topic, as far as I know, Visio is the only official tool for which shapes (server, storage, networking, etc) are provided. Maybe there is a FOSS equivalent of Visio that will enable you do generate the required diagrams? Visiocafe is the source of all HP shapes, and it seems to be updated often enough.