Adding audio or video podcasts to your blog or web site is a great marketing strategy, because podcasts add value to your site and encourage people to return on a regular basis to see what new content you’ve posted recently.

But trying to find podcasts that are relevant to your niche website is reminiscent of the early days of the Internet. Podcasts have been subjected to the same primitive search through categorization… until now.

Podzinger is a cool new audio and video search engine that allows you to find relevant audio and video podcasts. And you can perform the search right from your Virtual Real Estate Toolbar.

Type in a word or terms into the toolbar’s search box and select Content > Audio > Podzinger to search for audio podcasts, or Content > Video > Podzinger to search for video.

Podzinger not only finds the relevant podcasts, but also highlights the segment of the audio in which they occurred. By clicking anywhere on the results, the audio will begin to play just where you clicked. There are also controls that let you back up, pause, or forward through the podcast. Or you can download the entire podcast.

To show you what I mean, here’s a screencap of the first result I got when I used Podzinger to search for the keyword phrase “green tea diet”:

As you can see, there is the Download button below the controls. Press it to download the podcast. Now you can insert it into your website or blog.

Several other services offer podcast searching, including Podscope and Blinkx.tv, but none offer such sophisticated text conversion along with equally convenient playback options. As the universe of podcast content grows, services like Podzinger are becoming increasingly valuable for niche website building.