Vasco

Hello there.

1) That's a common lie that has been spread all over. The ONLY way you can get a Deoxys is by using an Action Replay and/or getting a special Ticket (I'll give more details bellow).

2) You can get Wailmer ANYWHERE on the map (sea areas, of course), but you'll have more luck over Routes 125 and 128; you must use the Super Rod. As for TM Dig, go to the furthest house west (route 114) in Fallarbor town. Talk to the little kid who's inside.

3) It's a pretty long explanation, so I'll simply say this: it's purely based on luck. Your odds are of 1:65546, so just keep insisting and talk to him once everyday. Honestly, I don't think it is worth the trouble. The only Pokemon you'll find there are Wynaut. Yes, there's a rare Berry as well, but is it really worth your time? Up to you.

4) You can't, unfortunately. Not anymore. They were given out at Nintendo Events (Events that occur at Toys'r'Us or Gamestop a few times per year). Considering Sapphire is a relatively old game, those Tickets aren't obtainable from Nintendo Events anymore. You CAN use Action Replay codes, though. Hope I've helped, good luck. :)