About a week ago I started trying to do searches on Limewire and nothing is coming up. Not a single search result. None of my settings have changed, I haven't installed or uninstalled any new security software and I already uninstalled and re-installed limewire and no luck. I have used Limewire for several months and never had a problem with it until now. Someone please help!

Try this: Problems with the search

And if that's no help, delete LW's preferences folder when LW's properly closed. See point 3 here & also point 2 if you've used older versions of LW in the past (there could be a folder in either location).
Fixes for LimeWire
This will kill all of your settings within options, you'll have to go back through afterwards & reset things.

If neither of those help, please give us your details.
System details - help us to help you (click here)
Is your connection to the network ok? How many green bars do you see?

I re-installed limewire and when I set up the initial settings again it was working. However, once I shut down and came back to the computer to use it later in the day, limewire wasn't bringing up any search results again. I tried everything on the fixes page and even tried to reconfigure my firewall, but it didn't work. I'm running Windows ME, plenty of hard drive space, 512MB Ram, At&t DSL internet, I have Limewire version 4.12.11, Java version 1.6.0_01, 2wire modem, the test worked and I have been using limewire for quite some time. What else could it possibly be?

Try this version of Java, some people have had trouble with 1.6.0_01. Use the JRE offline installer & remove your current Java version before you install this one.
Archive: Download Java 2 Platform Standard Edition (J2SE) 5.0 Update 11

Did you actually delete the preferences folder, or just reinstall LW? Deleting the prefs folder(s) has helped other people who've had this problem. If you're not sure of your settings within LW's options...make a note of them all beforehand, so you can reset things afterwards.

If you're still stuck then please give us your details. Click on the blue link in my earlier post to see the info we need.

Wait!!! First thing you should do is Uninstall all versions and updates of Java then uninstall Limewire and then Reinstall Limewire only. Limewire will install Java for you and this should fix the problem. DO NOT update your Java after this or you will have to do the same thing all over again. It worked for me.