Does anybody know how to do this? I'm sure there is a Google command like site: but I can't recall what it is. I want to see what actual backlinks a competitor has.
Google won't show you all that data. It's very limited.
link:
The query [link:] will list webpages that have links to the specified webpage. For instance, [link:www.google.com] will list webpages that have links pointing to the Google homepage. Note there can be no space between the "link:" and the web page URL.
You won't see very much of your competitor's shit doing it that way though. You should use something like seospyglass.
backlinkwatch is free if your just looking for a general idea of what's going on. Not so good for checking out what the quality of the links are though.
I have been doing that checking for competitors backlinks for quite long already. What I usually do is to grab some tools which are free to download on my PC. Try to search on competitors backlinks checker tool. Hope you find this very useful.
I used both SEO Spyglass and the search query link:[domain] and just note that searching link:domain misses many of the results you will find when you run the domain in SEO Spyglass. I really recommend using SEO Spyglass.