Amazon, Knight, Warlock and Priest are PC/NPC classes, so you would use the rules from the races database and then figure it out for the appropriate level.

There is a medusa in the default monster database, so you can look there for her.
Medusa:
\(BEGIN)
name = Medusa
icon file = icon_Medusa.png,0,2,48,48,0,1,2
miss sound = sound_Miss.wav
hit sound = sound_Hit.wav
move sound = sound_MonsterMoveStep.wav
death sound = sound_MonsterDeathMedium.wav
intelligence = 13
armor class = 5
movement rate = 9
hit dice = 6.000000
treat HD as hit points = yes
hit dice bonus = 0
THAC0 = 13
magic resistance = 0
size = medium
morale = 35
experience point value = 869
Special Ability = monsterLevel,6
Special Ability = monster_CombatantAlignment,evil
Class = Fighter
Race = Monster
form = none
penalty = none
immunity = none
Misc Options = none
item = monsterMedusaFleshToStone
attack = 4,1,0,attacks,monsterPoison
attack = 1,1,0,gazes,
Undead = none
\(END)
Erinyes:
\(BEGIN)
name = Erinyes
icon file = icon_Erinyes.png,0,2,48,48,0,1,2
miss sound = sound_Miss.wav
hit sound = sound_Hit.wav
move sound = sound_MonsterMoveStep.wav
death sound = sound_MonsterDeathMedium.wav
intelligence = 14
armor class = 2
movement rate = 12
hit dice = 6
treat HD as hit points = yes
hit dice bonus = 3
THAC0 = 13
magic resistance = 30
size = medium
morale = 30
experience point value = 29500
Special Ability = monsterLevel,7
Special Ability = monsterCombatantAlignment,evil
Special Ability = monsterWeaponImmunity,1
Special Ability = Summoned,plane
Class = Fighter
Race = Baatezu
form = none
penalty = none
immunity = death magic + confusion + none
Misc Options = none
item = none
attack = 4,1,0,attacks,
Undead = Special
\(END)
Draconians:
\(BEGIN)
name = Aurak
icon file = DEFAULT
miss sound = DEFAULT
hit sound = DEFAULT
move sound = DEFAULT
death sound = DEFAULT
intelligence = 16
armor class = 0
movement rate = 15
hit dice = 8.000000
treat HD as hit points = yes
hit dice bonus = 0
THAC0 = 13
magic resistance = 30
size = medium
morale = 40
experience point value = 2160
Special Ability = monsterLevel,8
Class = Fighter
Race = Monster
form = none
penalty = none
immunity = none
Misc Options = none
item = none
attack = 8,1,2,attacks,
attack = 8,1,2,attacks,
Undead = none
\(END)
\(BEGIN)
name = Baaz
icon file = icon_DraconianBaaz.png,0,2,48,48,0,1,2
miss sound = DEFAULT
hit sound = DEFAULT
move sound = DEFAULT
death sound = DEFAULT
intelligence = 9
armor class = 4
movement rate = 6
hit dice = 2.000000
treat HD as hit points = yes
hit dice bonus = 0
THAC0 = 19
magic resistance = 20
size = medium
morale = 40
experience point value = 90
Special Ability = draconianBaaz
Special Ability = monsterLevel,2
Special Ability = monster_CombatantAlignment,evil
Class = Fighter
Race = Monster
form = none
penalty = none
immunity = none
Misc Options = none
item = none
attack = 4,1,0,attacks,
attack = 4,1,0,attacks,
Undead = none
\(END)
\(BEGIN)
name = Bozak
icon file = icon_DraconianBozak.png,0,2,48,48,0,1,2
miss sound = DEFAULT
hit sound = DEFAULT
move sound = DEFAULT
death sound = DEFAULT
intelligence = 14
armor class = 2
movement rate = 6
hit dice = 4.000000
treat HD as hit points = yes
hit dice bonus = 0
THAC0 = 17
magic resistance = 20
size = medium
morale = 40
experience point value = 250
Special Ability = draconianBozak
Special Ability = monsterLevel,4
Special Ability = monster_CombatantAlignment,evil
Class = Fighter
Race = Monster
form = none
penalty = none
immunity = none
Misc Options = none
item = none
attack = 4,1,0,attacks,
attack = 4,1,0,attacks,
Undead = none
\(END)
\(BEGIN)
name = Kapak
icon file = icon_DraconianKapak.png,0,2,48,48,0,1,2
miss sound = DEFAULT
hit sound = DEFAULT
move sound = DEFAULT
death sound = DEFAULT
intelligence = 9
armor class = 4
movement rate = 6
hit dice = 3.000000
treat HD as hit points = yes
hit dice bonus = 0
THAC0 = 18
magic resistance = 20
size = medium
morale = 40
experience point value = 145
Special Ability = draconianKapak
Special Ability = monsterLevel,3
Special Ability = monster_CombatantAlignment,evil
Class = Fighter
Race = Monster
form = none
penalty = none
immunity = none
Misc Options = none
item = none
attack = 6,1,0,attacks,
Undead = none
\(END)
\(BEGIN)
name = Sivak
icon file = DEFAULT
miss sound = DEFAULT
hit sound = DEFAULT
move sound = DEFAULT
death sound = DEFAULT
intelligence = 14
armor class = 1
movement rate = 6
hit dice = 6.000000
treat HD as hit points = yes
hit dice bonus = 0
THAC0 = 15
magic resistance = 20
size = medium
morale = 40
experience point value = 500
Special Ability = monsterLevel,6
Class = Fighter
Race = Monster
form = none
penalty = none
immunity = none
Misc Options = none
item = none
attack = 6,1,0,attacks,
attack = 6,1,0,attacks,
attack = 6,2,0,attacks,
Undead = none
\(END)
Giant Pseudoscorpion:
No idea, will stats for a giant scorpion help?
Allosaurus:
I can't find stats for this, but I can for a Tyranosaurus Rex