In savage worlds can you make tricks at range? It really doesn't say any kind of range for the trick to function at, just that you need to have a good description at what you are trying to attempt.
Yes. If you come up with some action to take in combat and it turns out that a Trick is the best mechanic to represent that manoeuvre, then the effective range is exactly what makes sense for the fictional action.
The mechanics don't dictate a range because that would be too restrictive on what would count as a Trick, so instead range restrictions are taken care of by the requirement that there is solid fictional description justifying invoking the Trick rules. The range limit is then defined by the description.
In principle anything is possible with a Trick. A Trick is a GM's call: the GM has to decide whether the Trick is based on Smarts or Agility, and whether it is possible at all based on the description. Any range could in principle be possible, just line of vision could be enough (for example, to blind a foe by reflecting sunlight with a mirror), and sometimes not even that would be necessary (for example, to distract a foe by yelling 'Haha! Look behind you!").
For additional clarity, I will add that the Savage Worlds Deluxe rules provide an example that can clearly work at any distance as long as there is line of vision:
Buck is backed into a corner by a very large and dangerous thug. Our hero pulls the oldest trick in the book. He says “Hi Virginia!” and pretends to smile at someone behind his less-than-brilliant foe. He and the thug both make Smarts rolls...