1.Buy the Battler Card.
2.Go to this place where you can find this virus:
3.You need a Battler Card to make these viruses appear. Any time after you receive your second Cross, jack into the blackboard in Class 1-2 at School. There you will find a red Punk Navi. Pay him 2000 Zenny to receive your Virus Battle Card and two viruses, Mettaur and Gunner. Now you can start collecting viruses.

The viruses with the name "Rare" are located in the area at the right side.

Mettaur - Central Area 1
Piranha - Seaside Area 1
Heady A - Underground Area 1
Swordy - Underground Area 1
Killer Eye - Underground Area 2
Quaker - Seaside Area 3
Catack - ACDC Area
Wind Box - Mr. Weather Computer 1
Champy - Central Area 3
Old Stove - Central Area 3
Haunted Candle - Graveyard
Puffy - Seaside Area 2
Starfish - Aquarium Computer 3
Earth Dragon - Graveyard
Scare Crow - Sky Area 2
Pulse Bulb - Mr. Weather Computer 3
Big Hat - Undernet Area 1
Bomb Corn - Judgement Tree Computer 2
Shrubby - Judgement Tree Computer 3
Honey Bomber - Judgement Tree Computer 1
Gunner - Central Area 2
Fighter Plane - Sky Area 1
Dark Mech - Undernet Area 2
Snake Arm - Graveyard
Armadillo - Green Area 2
Cragger - Judgement Tree Computer 2
Nightmare - Underground Area 2
4.To easy get all this viruses, here I called it the Cyber Attracted-Cloning I invent it and it works!
5.Heres the procedure!
6.Save your Game.
7.Go to Library ( and If the virus have 1 2 3 version like metaur and its reflecter 1 2 & 3)
8.Click the 3rd version then the 2nd Version then the 1st Version
*here example:
Reflecter1---- 3rd click
Reflecter2----2nd click
Reflecter3----1st Click

9.After clicking all. A Virus that has only one version clicks it 3 times.
10.Save the Game and let approximately turn it off in 3 second.
Well if not works turn it off and try to find another virus...
11.Turn on again the first virus that you have is rare and ta-da your going to complete it!

I hope I help!

(This Cloning procedure is only just invent so don't expect it works...
Because I try it and it works to my MegaMan Game...)