Most times, it's not hard to find the video you're looking for.
Especially if you are looking for any videolinks, a simple google search will suffice, like
funny +filetype:wmv.
Or, in the page containing the videolinks, you rightclick on a link and paste it in the container creator. Sometimes you even have to look in the sourcecode of the webpage, but mostly that's all.
If you can't find it, there's several tools to give it another try.
First, of course, there's
URLsnooper.
URLsnooper is a piece of donationware (freeware unless you think it's worth your money) I brought up in the fabchannel article, which captures media-urls that are loaded by webpages. Give it a try, it looks something like this:

If that's too complicated or doesn't work, you can try a firefox plugin called
unplug, which basically, once installed, gives a page with medialinks for each website you want:

Now, you surf to a site, press the button, and unplug gives you the links.
Just copy and paste them into your containers.
A bit different are embedded links and the like. Firefox has a plugin to deal with that also: it's called (very catchy)
MediaPlayerConnectivity. When installed, it replaces the video's on the pages you visit with a black MPCbutton and some other handy right-click stuff. Basically, with this, it is really easy to copy-and-paste andy video-URL on any website. The trick is (in my humble opinion) to swich off the MPC for all filetypes, and when you want a video and cannot easily get the URL, switch the filetypes on and refresh the page. Once at work, it looks like this:

Still, the problem of getting the vids in containers is persistent. Or is it? I dumped the links in the Zapper in quite some formats, and one actually worked.
In full screen, presented to me with great awe, with only the grey playbar on the bottom to remind me it's a google-vid, there it was: an swf file played on the zapper!!!
Apparently, the trick is to associate swf files in the zapper with MediaPlayer BUT CREATE THE LINKS IN THE CONTAINER (or in the Zapper Media Manager) AS WEB LINKS!!!
The code will be like this in the container:
<Item Type="BROWSERURL"><Name>IT'S NAME</Name><URL>ACTUAL URL (being 12 lines long)</URL></ITEM>
I'm not sure it's ment to be this way, but hey, it apparently works.
The toughest thing would be to get videocontent from within flash-applications, like from the dreaded fabchannel, starting to play full screen.
when you really want the video, I'd go for downloading (ripping) the content instead of trying to find the link, which is way more easy: look
here for instance).
While digging into this matter, I stranded in decompilers, ASP hacks, PHP reverse-tools: not worth the effort. In that case, you're better off getting the Opera plugin to work and watching the flash video's on your Zapper through that route.
But until now Fabcahnnel won't play fullscreen.
Grr