You sure have many options to use to find your own stuff from your local computer, for example, Google Desktop Search, MSN Desktop Search, or even run local built-in search function. But when it comes down to find your stuff in your inbox from your Outlook, Microsoft Lookout is my choice.
Microsoft Lookout is a free Outlook add-on that provides better indexing and retrieval capabilities than Outlook's standard Find, Advanced Find, or Search Folders features can provide. And one of the benefitial over Googl Desktop Search is that it indexes email attachments and Exchange public folders, which mean that it works with Exchange server and you can search by the name of the attachments.
click here to download the Microsoft Lookout