Dragon Ball Z Budokai 3

The cards can either be bought in the shop after you spend a certain amount there, or found in Dragon Universe by a character of high enough level. In DU, the cards appear at the same place for each character every time. For Goku, (probably the easiest character to get them with) they appear on an island just West-Northwest of the main continent. It doesn't matter how many times you go through DU, it is your character level that matters.

Silver Membership Card Character Lvl 2+, or spend 1,500 zenie in shop or have budokai 2 save.
Gold Membership Card Character Lvl 15+, or spend 100,000 zenie in shop.
Black Membership Card Character Lvl 30+, or spend 250,000 zenie in shop.

Go to Dragon Arena, pick your Saibamen. Then fight the highest level Yamcha you can fight. If you selfdestruct on him he will automaticly die as he does in the series.

Beat Dragon Universe with one of the 11 characters on the Z 3 difficulty setting.

You cannot buy the next tournament in line even if you beat the previous one unless you have the required amount of characters. Novice requires 8, i think you start off with that many anyways. Adept requires 16, playing through dragon Universe with Goku should get you about 8. Advanced requires 32, almost all of the characters in the game are required, and for some reason doubles and triples of the same characters are counted as seperate people ( kid Gohan, teen, and adult, as well as the Buus and the 2 Trunks'). NOTE: someone gave a list of how to get the characters, which although is very useful, is not 100% acurrate. For example, you do not have to defeat Broly twice to get him, although in some circumstances like the diffuculty level, you might. And Videl ccan be found by playing Gohan and looking on one of the islands at the south end of the map. It will not be a red dot and I'm not sure when you get her except it's at the very beginning. You will know you will get her because you will be talking to Yajerobi.

Here is the transformation list for every character.

Goku: Kaioken, Super Saiyan 1,2,3,4
Kid Goku: none
Kid Gohan: unlock potential
Team Gohan: Super Saiyan 1 & 2
Gohan: Super Saiyan 1 & 2, Elder Kai Unlock Ability
G Saiyanan: none
Goten: Super Saiyan
Vegta: Super Saiyan 1, 2 & 4
Trunks: Super Saiyan 1 & 2
Kid Trunks: Super Saiyan
Krillin: unlock potential
Piccolo: Sync with Nail, fuse with Kami
Tien: none
Yamcha: none
Hercule: high tension
Videl: none
Supreme Kai: none
Uub, Bardock, Raditz, Nappa, Ginyu, Recoome, #16, #17, #18, Gero, Majin Buu, Super Buu, Kid Buu & Omega Shenron: all none
Frieza: 2nd, 3rd, final, 100% & Mecha Forms
Cell: 17 absorption, perfect form, super perfect form
Dabura: Demonic Will
Cooler: Final & Metal forms
Broly: Legendary Super Saiyan

Buy it for 50,000 for each character after you unlocked all character.

The most recommended character in the game is Kid Buu. If you choose him in duel mode or dragon arena, be sure to put 'Kamehameha', 'Vanishing ball', 'Warp Kamehameha' and senzu bean in the skill list. With this you'll have 78.2 percent of winning.

Dabura:In story mode defeat Dabura with Teen Gohan

Great Saiyaman:In story mode defeat cell with Teen Gohan or Kid Gohan

Bardok: In the beginning of DU fly over to Raditz's spaceship, you should see a ???. Enter it and you should get him.

Brolly: Beat him on the second time through as Goku instead of Kid Buu.

Gogeta Capsule: On a time through as Goku/Vegeta.Instead of fighting Uub/Brolly,you receive an invetation from their sons to fight in a fusion. Just win that fight.

Cooler: After beating Frieza under where you beat him, should be SS Vegeta. Beat him and Vegeta will tell you about him. Go to Cooler's red mark and beat him.

Vegeta: Play through dragon universe with goku

Fat buu: Play through dragon universe with goku

Kid buu: Play through dragon universe with goku

Kid Goku: Complete Dragon Universe mode with Broly

Teen Gohan: Complete Dragon Universe mode with Kid Gohan

Gohan: Complete Dragon Universe mode with Teen Gohan

Great Saiyaman: Complete Dragon Universe mode with Gohan

Goten: Defeat Goten in Dragon Universe mode with Gohan

Vegeta: Defeat Vegeta in Dragon Universe mode with Goku

Trunks: Complete Dragon Universe mode with Vegeta

Kid Trunks: Defeat Majin Buu in Dragon Universe mode with Vegeta

Videl: Go to plains (point 4 on map) with Gohan

Captain Ginyu: Defeat Captain Ginyu in Dragon Universe mode with Goku

Recoome: Defeat Recoome in Dragon Universe mode with Goku

Frieza: Defeat Frieza in Dragon Universe mode with Goku

Android 17: Defeat Android 17 in Dragon Universe mode with Piccolo

Android 18: Complete Dragon Universe mode with Krillin

Dr. Gero: Defeat Dr. Gero in Dragon Universe mode with Yamcha

Cell: Defeat Cell in Dragon Universe mode with Teen Gohan

Majin Buu: Defeat Majin Buu in Dragon Universe mode with Goku

Super Buu: Defeat Super Buuin Dragon Universe mode with Goku

Kid Buu: Defeat Kid Buu in Dragon Universe mode with Goku

Uub: When fighting kid buu use the spirit ball technique and win

Vegito(Goku): Defeat Super Buu as Goku in Buu's Body in DU

Vegito(Vegeta): Defeat Super Buu as Vegeta in Buu's Body in DU

Gogeta (ssj2): After defeating Broly In Dragon Universe Mode Defeat Gotenks At The World Tournament Arena

Gogeta (ssj4): In Vegeta's DU instead of fighting Kid Buu go find Goku who is now a Super Saiyan 4. Defeat him and you will get this Fusion.

Trunks (young): Defeat Majin Buu in Dragon Universe mode while playing with Vegeta.

Gotenks: Buy in the capsule shop.

Dr. Zoidberg: Defeat Syn Shenron in his Omega form using base Kid Goku.

Android 16: In Krillin's Dragon Universe mode. Got to one of the islands near Roshi's house and take hime to Bulma in West City for repairs to get him.

Oceanic Shenron: Beat Omega Shenron with broly 5 time without losing

Kujila: Get everyone to at least level 10 in the Dragon Arena

Cell JR: Piccolo will randomly appear in Dragon Arena, beat him to get Cell JR.

Beat Dragon Universe with all of the characters to unlock Dragon Arena.

In dragon universe mode, you can unlock 21 original voice data in the bonus section, by using special abilities with the opponents with all the characters.

voice data 00: goku vs raditz - use kamehameha
voice data 01: piccolo vs raditz - use special beam cannon
voice data 02: tien vs nappa - use ki blast cannon
voice data 03: kid gohan vs nappa - use masenko
voice data 04: krillin vs frieza(third form) - use destructo disk
voice data 05: goku vs frieza(100% full power) - use super saiyen
voice data 06: yamcha vs dr. gero - use senzu bean
voice data 07: piccolo vs cell - use fuse with kami
voice data 08: vegeta vs cell(absorb 17 form) - life more than 2500
voice data 09: vegeta vs cell(perfect form) - use final flash
voice data 10: teen gohan vs goku - use super sayan
voice data 11: teen gohan vs cell(super perfect form) - use father-son kamehameha
voice data 12: vegeta vs majin buu - use final explosion
voice data 13: goku vs majin buu - use super sayan 3
voice data 14: win after time limit passes 60
voice data 15: gohan vs super buu - use elder kai unlock ability
voice data 16: goku vs kid buu - use super spirit bomb
voice data 17: vegeta vs ss4 goku - use super saiyan 4
Voice data 18: SS4 Gogeta vs. Omega Shenron/Earth. Use 100X Big Bang Kamehemeha
voice data 19: broly vs gohan - use gigantic meteor
voice data 20: uub vs goku - use ki cannon