3rd Gen Encountering Wandering Legendaries

Hi guys! I just finished both my FireRed ver. and Emerald version and have begun collecting the legendaries to complete my pokedex. Im just having problems encountering both Entei on FireRed and Latias on Emerald. It seems they dont show up on the radar like how it does on Pearl (though I could be wrong). So I was wondering if anyone can give me tips as to what is the best way to encounter these pokemon in the wild.

Being specific would be great if you can spare the time (route#, items needed, best strategy to capture, etc). Please share your experiences as to how you encountered these stray pokemon. Thanks a lot!

Your better off NOT looking for the legendaries. Just run around in the grass on a path and you'll find them. I believe Lati@s sticks to three specific paths (but I'm not sure which ones) so just run around over in those paths (maybe on your way between cities) and Lati@s will come to you.

I don't have FR/LG so I don't know where you could find the legendary dogs. Or if they stick to a specific pattern like Lati@s.

Best items needed: use Ultra Balls/Master Ball to capture unless you don't want to waste it on a Lati@s. I believe there are other types of Poke Balls you could use but I'll have to check the FAQs.

Because Lati@s keeps its status change/HP level until you faint/capture it, you shouldn't be in much of a hurry in looking for it or trying to capture it upon first encounter.

EDIT: Forget about what I said before if you're impatient and want to find Lati@s right away, go here.
https://www.pokecommunity.com/showthread.php?t=185

Cool thanks for the tips guys. I caught Latias just running around route 129 trying to catch a Wailord for the Regis quest. It was by accident. I tried to do the same for Entei but still no luck but I'm gonna keep trying.

Well I managed to catch a Raikou in my first FR game and I'm currently trying to catch an Entei the same way. Try moving Entei into Route 7 between Celadon and Saffron Cities. It's a small route that way you don't have to search as much as you would on a different route. Make sure you have someone with Hypnosis or Sing (Sleep prevents running for 2-5 turns), has Mean Look (prevents running all together) and has the ability Soundproof (prevents Entei from using Roar-is Roar is used, you are out of luck). After that, try catching them with an Ultra ball. Good luck with that.