I've searched long and hard for pikachu in the safari, i've used sweet..

What legendary bird are you talking about? You should find Pikachu in the area you first see. Special abilities you can use:
Pressure/Arena Trap-makes wild Pokemon more common.

Static-makes wild electric-type Pokemon more common.

CoumpoundEyes- makes wild Pokemon have [I think] an 80% chance of holding an hold item. Good to get a Pikachu with a light ball which you can trade to an emerald, breed while female Pikachu is holding it mating with a male Ditto/Raichu/Pikachu, then hatching the egg to find that Pichu has volt attack then trade it back.

And for more, go to http://www.serebii.net/emerald/ability.shtml

I'm sorry but the last of the Legendary Birds, Ho-Oh and Lugia, were left "flailing" in Johto, but you only travel around in one country in Ruby, Hoenn, and the closest Pokemon to the Legendary Birds are the Pshycic/Dragon siblings Latios and Latias, kind of like a cross-breed between a Legendary Bird, and Mewtwo, and the Legendary Dogs, because if you encounter them, they run away, and when you encounter them, heres some tips on how to catch them: Bring a strong Wobbufett, say Lv. 45 or 50, because "The Latis" are Lv. 40 maybe 30, I dunno, I can't remember, either way, bring a strong Wobbafett to the front of your party, because Wobbafett has the "Shadow Tag" special ability, which can trap them, also, "Arena Trap" won't work because of the "Latis" "Levitate" ability. This way you can trap'em so you catch'em, I suggest, you get a Pokemon with False Swipe, like Zangoose, then, the last time you meet up with them, put Wobbafett in front so as to make use of his special ability.
As for the Pikachu problem, patience, just go into the Safari Zone, immediatly go into some grass, and just use Sweet Scent, occasionally changing positions, and I have about 5 Pikachus so I know what I'm talking about.

Hope I helped,
CrystalTitan1

When you enter in; in the first patch of grass you can find a pikachu just have to be patient.