I've done plenty; there's a lot of bugs, and most importantly, if you're doing them for local Faction Influence, be aware that is apparently broken, and you may actually be
harming your faction by running missions. Indications are the rewards either aren't counting or are being given to different factions. Sigh.
Here's how Assassinations currently works with locating targets however.
1.) Using the discovery scanner will
sometimes, but only very rarely locate the body the spawn instance will be around. I am tempted to say this is now actually a bug and it's not supposed to do so now, given how rare it has been for me. I estimate under 1 in 20 appear, from how many I've done.
2.) Upon arrival, the best way is to drop onto the navigation beacon, and do a local scan of it. This will pin the exact location of the instance on your map, but you wont see them until you jump back up into supercruise. This will also locate the system for NPCs to meet if the target has moved.
3.) Don't expect to get a Chat window message about this. You might, but mostly you have to check either local Navigation, or the mission itself, or Galactic Map if desperate to be told where it is.
4.)
Sometimes you'll be in the right system, but it won't spawn even then. You can still locate it, but now you have to use the FSS. That wonderful, wonderful FSS.
Here's how. First tune it to the various signal sources. As you move around the map, the arrows pointing to a signal will turn orange; follow it to the Mission target. Zoom in on it to pin it on the map.
But if it's around a planet, you'll need to look for the orange, but far too close to the colour of a Gas Giant icon on one of them, zoom in and navigate around each level of zoom, find the signal source and pin it again.
5.) Even then it may break. But you can still interdict the NPCs in supercruise; you can try and get them to respawn by dropping down and entering supercruise again, and if you're really lucky they'll spawn on you when you drop down. Try and stay away from major bodies when doing this, as the NPCs will blindly fly into the stars and die, forcing you to drop down and up to get them back.
6.) If you don't want to play the fun interdiction game with its random working distance ("I can't interdict them at 10ls behind, but I can at 10,000 as long as they're slowing down or just feel like showing you pity?!") you can tell if they're trying to interdict you by targeting them, letting them pass you and watching if they immediately start turning. Fly straight ahead to try and give them a little distance as they'll overshoot and do the circle of shame just like players can.
7.) Missions for alternative targets do still apparently appear, but again rarely. I never take them because why would I if I've taken a specific factions mission in the first place? So I have no idea if those are working correctly or not.
8.) Head to the pinned instance as your final resort; interdictions will give you a small grace period of the lead Wing target only before the rest of the Wing appears, but the instance has them all ready when you arrive.
9.) If you're doing the "Massacre" missions however, the initial instance spawn may not be the Mission Target faction; in general they should jump in when you start shooting the Wanted that are there however.
And that's my experience of these missions so far! Hope that's useful.
