How to find Titans???

You have to search for them in the realm. There is also a chance that you can spawn a titan based on what level monsters you hit. I'm assuming (I have to say I assume since I didn't ask ATA specifically and am just taking this knowledge from what I saw happen, but I didn't do a clear cut study on it) they make it so if you hit a monster that spawns it, it's not going to be more than you should be able to hit. Like if you hit a level 4 monster, you shouldn't spawn a level 2 titan because realistically, if you are hitting those monsters, you probably aren't at a high enough TH to hit a level 2 titan anyway. If you and the people around you hit enough monsters in the same level ranges, you'll be more likely to see one you need spawn. Just keep hitting monsters, and keep your eyes peeled for those titans. Someone in your clan may come across one...hopefully they are nice enough to share the coordinates with the clan...that's what clans are for, sharing.

My guess would be since with research, you can't hit a titan level 2 until you reach TH 18, you shouldn't be able to spawn a titan level 2 until you at least reach TH 18, and at 18, you can research to do LVL 6 monsters, so anything below level 6 monsters may possibly be able to spawn a Level 1 Titan...
Titan 1
TH 10-17
Monsters 1 (or 3)-5
(I'm not sure if monsters below 3 will spawn one, or if 3 will, but you can't hunt a titan until you reach TH10...so...)

The research for a Level 2 Titan isn't available until you reach TH18, so with that said, at TH18, you can research to hit Level 6 monsters. You can't hit a Level 3 Titan until you reach TH25, and at TH25, you can hit level 9 monsters...so I'd assume that anything below 9, but above 5 would spawn a level 2 titan...(6-8)
Titan 2
TH 18-24
Monsters 7-8

And what's left is level 9 monsters.
Titan 3
TH 25
Monsters 9


These are all my GUESSES on what level monsters will spawn them.
You will also have titans spawning randomly throughout the realm as usual...but this is also another way they may spawn. It's not going to be every monster you hit...you may be hitting monsters all day and still not spawn one, then one day, you spawn one on the first one you killed... It's random as well, but better than before. You just have to hit monsters and be on the lookout...and don't forget to have your clannies share the coordinates of those they find...and you do the same.

 

You cannot research lv7 Monster hunting until TH20. Also, lv6 monsters can spawn lv2 Titans

 

Good catch, lol. I even had More Unlock Orders open while I was typing that, lol. (Gonna blame this one on distractions, lol. I was trying on a lot of clothes while I was typing that.)