I've been looking for a while for a nice simple schematic drawing tool for tube amps. I just downloaded Tube Pad 5.0 and it appears to be a bunch of images that you can drop into your own drawing program. I've been using them in Visio.TubePad 5.0
Here is download off of my site if the link above doesn't work. TubePad 5.0 - copy at harpamps.com. The download at their website was very slow.
