(disclaimers at end)
You can avoid the majority of fake files simply by the terms you search with. Let's say you are trying to find the song "Up The Creek" by the band Locomule. Instead of looking for "Up The Creek", look for "Creek Up The" etc. Any result that comes back with the title mixed up like you searched for... AVOID! The real file will show up in your results with the title words in the correct order. This works cause the virus spammers use some app to catch search terms, and rename their viruses thusly. For titles with only one word such as "Firedog" just type in part of the word, ie. "Firedo" as a search term. Again, avoid any results that do not add the missing letters from the correct title. These tips alone can save you a lot of trouble. If your p2p program allows, you can add the people *(isps) offering these fake files to your banned/filter list. Care should be taken to only add isps that provide garbled name results, ie.. if you find a virus with the correct title "Firedog" and ban everyone supplying that file, you will be banning many legtimate users who are unknowingly sharing virus files and therefore you will actually be helping the spammers. These forums are chock full of other tips (avoiding files under 2M, files with excessive instances found, .wma and .wmv type files, etc)

Here's one I didn't see.. Lets say you've been getting various songs. Now you search for a song you don't have yet, "Down the Creek". If you see versions of "Down the Creek" in your results that are marked as already downloaded, they are actually viruses that you already have in your Saved folder under alternate names. Remember, these viri I'm discussing have titles that change to match your search terms. Find the bad files you already downloaded by matching the file sizes (from the p2p search results against your Saved files) and delete the saved files (viri) from your Saved folder. Empty your recycle bin also to make sure you don't accidentally restore the viruses later... (2 days later) "hey, who deleted that song I wanted?"

One trick the spammers use is to add some words to your search title. I looked for the song "lkjhg" (obviously and intentionally NOT a real song) and got a result of 18 copies of "lkjhg greatest hit 2009" so now I know to avoid ANY future search results with the words "greatest hit 2009" at the end. Here are a few other "added title words" that popped up... "lkjhg (hot new track)" "lkjhg extended version" "lkjhg extended live version" etc.

On one hand, it would seems that Limewire/Gnutella/etc developers could institute some feature to automatically weed out these spammers but on the other hand, they would just come up with new, possibly more difficult to detect ways of inserting viri files. So don't be an idiot and blame the developers for viri problems. Blame the success of these awesome, optionally FREE apps and stay one step ahead by keeping yourself informed. Use the content filters and this compedium of knowledge because ultimately, all responsibilty falls on the user. If you doubt that, blindfold yourself and go for a drive. Then, after you wreck, sue the automible manufacturer and see how that works out for you.

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My tips come from years of Limewire use. I am currently running the free version 5.1.2 on a fully updated Windows Vista over a broadband connection. I use the term "viri" as a general term for any sort of file that is not the file you intended to download. The file names I used in this post were all made up, not real files. These tips apply to all searches, not just songs. Lastly, sorry for any reposting or crossposting. I did fairly extensive searching through various forums before posting this. Peace all.