Can anyone tell me how to catch a Latios?

Just track it with your pokedex,and go to where it goes.

Well, there isn't really an easy way to catch Latios, except for using a Master Ball, but you should save it for Rayquaza. Anyways, here's one way. Since you already caught it, you can see where it's at, by looking at the Pokedex. When you're on the same route as it, use a Repel, and have your first Pokemon a Pokemon that is one level lower than Latios, and knows a Sleep move. When you get into a battle with it, use the move, lower it's HP, and just keep throwing Ultra Balls. I don't know how long it will take, but it will proabably take a while. Good luck!

Hey mate all you need to get latios is a master ball but if you do not have that you need a high level pmon and try your best to get it

GOOD LUCK

Well first you need to go to the place that you saw latios first. Save and turn off the GBA then turn it on and check if latios is there. Keep trying untill it shows up then search in the grass and use a master ball on it.

The other people that answered had atleast one thing wrong. Use your Masterball on Latios, Iv'e caught Rayquaza 8times(My idiotic little brother deletes my character:(), and Iv'e never one used a Masterball. And, Rayquaza doesn't run away on the first turn. Although catching him can be diffucult, don't use Masterball. The other guy just said catach, but he meant seen. Anyway, if youu don't have Masterball, it's not over.Requirements: Catch a Wobbufet and raise it to level 50. Shadow Tag prevents Latios from running away. This can also work with certain Trapinch, but Wobbufet can take more hits. And I believe there is an Item that can put the opponet asleep, but you can also use an Oddish-Gloom-Roselia etc. But there moves aren't high accuracy, so I'd use the item. Buy enough of those items to last quite a few turns, and buy about 10 Timer balls, 3Nest Balls, 30 UltraBalls, And 15 PokeBalls. Finding Latios:But that's how to catch him, and to find him is a different story. What I do is get my stuff ready, fly to Pacifidlog, check my PokeDex to see wehere he is. Do this as many times needed until he is right next to the town. Make sure you have a Pokemon with Surf. It make take a little chasing, but you should be able to end up catching him. I'm still trying as I speak, and I'm making up these words as I go...But they sound pretty good, so, I'll try it. I just have a lvl 30 Wobbufet and some balls, thats bout it.
How long it would take, hmmm, the time really varies. Once you you get the requirements, I'd say within a 30minute or less if your major lucky, but usually about 30min.-1hr. And 30 min.

Well you can use a Crobat to trap it by it's effect, Then weaken it down to the yellow or red area... Use maybe a great ball or a ultra ball. To catch it in a specfic area go to maybe a little grassy area on the left side of a little water way, Its at the bottom and located to the left side of the Day Care center, Save it there and turn it off and on until it's in your area, Then walk in that small patch of grass. He should appear.