Maybe [**DocFetcher**][1] could help.

From the home page:

> The application runs on Windows, Linux and Mac OS X, and is made available under the [Eclipse Public License][2].

> ###Notable Features###
> 
>  - **A portable version**: There is a portable version of DocFetcher that runs on Windows, Linux and Mac OS X. How this is useful is
> described in more detail further down this page.
>  - **64-bit support**: Both 32-bit and 64-bit operating systems are supported.
>  - **Unicode support**: DocFetcher comes with rock-solid Unicode support for all major formats, including Microsoft Office,
> OpenOffice.org, PDF, HTML, RTF and plain text files. The only
> exception is CHM, for which we don't have Unicode support yet.
>  - **Archive support**: DocFetcher supports the following archive formats: zip, 7z, rar, and the whole tar.* family. The file extensions
> for zip archives can be customized, allowing you to add more zip-based
> archive formats as needed. Also, DocFetcher can handle an unlimited
> nesting of archives (e.g. a zip archive containing a 7z archive
> containing a rar archive... and so on).
>  - **Search in source code files**: The file extensions by which DocFetcher recognizes plain text files can be customized, so you can
> use DocFetcher for searching in any kind of source code and other
> text-based file formats. (This works quite well in combination with
> the customizable zip extensions, e.g. for searching in Java source
> code inside Jar files.)
>  - **Outlook PST files**: DocFetcher allows searching for Outlook emails, which Microsoft Outlook typically stores in PST files.
>  - **Detection of HTML pairs**: By default, DocFetcher detects pairs of HTML files (e.g. a file named "foo.html" and a folder named
> "foo_files"), and treats the pair as a single document. This feature
> may seem rather useless at first, but it turned out that this
> dramatically increases the quality of the search results when you're
> dealing with HTML files, since all the "clutter" inside the HTML
> folders disappears from the results.
>  - **Regex-based exclusion of files from indexing**: You can use regular expressions to exclude certain files from indexing. For
> example, to exclude Microsoft Excel files, you can use a regular
> expression like this: .*\.xls
>  - **Mime-type detection**: You can use regular expressions to turn on "mime-type detection" for certain files, meaning that DocFetcher will
> try to detect their actual file types not just by looking at the
> filename, but also by peeking into the file contents. This comes in
> handy for files that have the wrong file extension.
>  - **Powerful query syntax**: In addition to basic constructs like OR, AND and NOT DocFetcher also supports, among other things: Wildcards,
> phrase search, fuzzy search ("find words that are similar to..."),
> proximity search ("these two words should be at most 10 words away
> from each other"), boosting ("increase the score of documents
> containing...")
> 
> ###Supported Document Formats###
>  - Microsoft Office (doc, xls, ppt)
>  - Microsoft Office 2007 and newer (docx, xlsx, pptx, docm, xlsm, pptm)
>  - Microsoft Outlook (pst)
>  - OpenOffice.org (odt, ods, odg, odp, ott, ots, otg, otp)
>  - Portable Document Format (pdf)
>  - EPUB (epub)
>  - HTML (html, xhtml, ...)
>  - TXT and other plain text formats (customizable)
>  - Rich Text Format (rtf)
>  - AbiWord (abw, abw.gz, zabw)
>  - Microsoft Compiled HTML Help (chm)
>  - MP3 Metadata (mp3)
>  - FLAC Metadata (flac)
>  - JPEG Exif Metadata (jpg, jpeg)
>  - Microsoft Visio (vsd)
>  - Scalable Vector Graphics (svg)


  [1]: http://docfetcher.sourceforge.net/en/index.html
  [2]: http://en.wikipedia.org/wiki/Eclipse_Public_License