I got bored and tried a couple different ways of making search plugins.
One worked, so here's a search for HLP's non-Google search, and one for the Wiki and Game Warden.
For the forums they may only work if you're logged in, so I'd suggest checking the box to "stay logged in"
if you don't already do that normally.
Extract to C:/Program Files/Mozilla Firefox/searchplugins (32bit XP) and restart Firefox, should work fine.
If you're on some other OS, try searching for the searchplugins folder, should have Google, Amazon, Yahoo
files in there by default so you know it's the right one.
Enjoy.

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