Shoutbox

I also think this could be quite useful. Having a large amound of sounds can make it extremely annoying to have to click the arrows many times.

Although not a total solution the the problem, you can increase the amount of sounds shown per page using the Plus! preferences (Plus>Preferences>General Options>Sounds) - this number can also be tweaked by using Messenger Plus! Tweak! to a much higher number (at the cost of sound panel loading time the first time it is loaded per convo).

There is no search option that I am aware of, however I also agree this could also be a somewhat useful feature for those of us with a large number of sounds. As an idea, perhaps the category combo in the sound panel could work as a seachbox also, so when you type something in, all sounds that contain a match or partial match could be displayed?