(You must have completed the game before you can get one of the Lati's,when you finish the game go downstiars and they'll be a report on TV watch it your mum will ask you what colour the pokemon on TV was Choose Blue or Red then go out) When you first find one of the Lati's you don't have to catch it, when it runs away you can check your Poke'dex and look for its area when you find it don't go after it keep on flying to the same town your in until it is close to the town then go out to it quickly and keep checking your poke'dex for its movements.