How do I catch Lapras in Four Island, exactly?

[BakuryuuTyranno]

I've been trying to capture a Lapras in Four Island but haven't even seen one.

The main problem is, I'm not sure exactly how to encounter one. I've seen a guide listin Lapras under Pokemon that could be caught by fishing, surfing and walking. Everything else on the list was only listed in one group. Since this was Bulbapedia, I thought it was one of those wikipedia joke edits random people make occassionally and had to double-check on an official game guide that Lapras is there at all. It is, but the guide doesn't give any detail on islands 4-7.

How exactly do I encounter a Lapras? I've been using the super rod mainly, but after encountering many Gyarados and a few Seadra but no Lapras, I'm starting to get the idea that's not how to meet one.

[Went]

Lapras appears only surfing, not fishing nor walking, in the zone where you battled the Rockets with Lorelei.
Probably some joker edited the info, as you say @_@

[Soufiane]

You can get one from someone in the Silph Co. department from some dude
I thought it was the 11th etage

[BakuryuuTyranno]

Okay thanks. Although... is it supposed to be ridiculously rare? I've seen several Tentacruels in that area so far, but no Lapras yet.

This is probably ludicrous but is there some other requirement? Defeating the Elite Four for the second time or something?

Maybe its just me. I haven't tried to capture a rare Pokemon in years. Maybe I forgot how long it takes.

[BREAKINGBEN]

There is a 1% appearance rate and a 045 catch rate.

[Lynnx]

It takes a lot of time, a lot of Ultra Balls and a ton of patience. Go to Icefall Cave and enter the room where you battled the Rockets. Surf into that little pool of water in the room and just go around and around and around. It takes forever but if you stick to it you should eventually meet one (I caught one after about ten minutes of circling that little puddle.)