It's called tinder because it's somewhat catchy, but that's really where the similarities end.
First, take a look at the list of players who are looking, here. (At the bottom, navigate to the "tst tinder" sheet.)
Secondly, take a quick look at the Registered Teams sheet and make sure they haven't already hooked up with someone else.
Then, contact them by the means they have provided. If you're lucky, they just might say yes!

Or, if nobody seems like a good match, sign yourself up through this form.
Or, you know, just respond in this thread and say you're available.
Once you've found your teammate, sign your team up here!
Good luck everyone!

Edit: Only 10 minutes too late, I realized I totally could've called it grinder instead. Damn!