I keep track of the party's doings on my Palm Pilot, including tracking XP by monster. Unfortunately it isn't 100% complete; I got my first Palm when they were 4th level so I missed 1st-3rd but I've got 4th-19th. It's pretty darn big too.
These are my notes so it's a little messy but should give you the idea.
critter cr xp
beetle 4 1200
spiders 2x2 1200
draconian ---
dragon ---
shield guardian 6 2400
violet fungus 3x3 2400
belkar 6 2400
dark mantles 6x1 2400
gargoyle 4 1200
phantom fungus 4 1200
grick 4 1200
cube 3 800
digester 6 2400
stirges 8x1/2 1600
bear 4 1200
ettercaps 3x4 3600
1 ettercap & 4 3600
6 Huge spider 6x4 7200
puma(lion) 3 800
2x assassin vine 2x3 1500
5th level (10,000xp)
troll 5 1500 (200)
ghoul wolves(1)x6+ghast (3)= 7 3000
cheetah x2 4 1100
minotaur/F:4 8 4500
3 hellhounds 5 3x2 1500
6 krenshar 5 6x1 1800
brigands 8 4250
--------------
(12,500xp)
cr 5 booth 1500
5xcr 5 sales 7500
0.5xcr7 1500=10500/7.5=1400
cr4 thief 1250
2 cr4 thieves 2500
Ulort (CR9) 6000/8.5=700(600) ogrin/ranger 2/sorceror 2=9
------- ------- -------15,000xp 6th
6x demon +1 imp=cr 5 (250)
Lord Geist Winterhaven
CR5 250
------- ------- -------(18,025xp)
module
traps 2xcr4 2000/6=333
no moundcr8 4500/0=0
vines cr2
9x2 9000/6=1500
party @ blevins 500 ------- ------- -------module=2,333 (20,358xp)
gibbering mouther cr6 1800/6=300
shale cr6 1800/6=300
boars 4x450 1800/6=300
------- ------- -------(21,258xp)
7th level
gray render =550
6x hippogrif 2364/6=394
archerai cr6 1400/6=233
shield guardian 3150/6=525
22,960
tower-traps & taflin =700
23,660
ankheg 4x3=2100/6=350
athac 2x7=4200/6=700
panther . 4=700/6=116
dragon/draconian 2x7=4200/6=700
inc 1866
25, 526
next level 28k-30k=2500-4500
behir 11hd 10=6300/6=1050
eoch & others 700
geist & horst 700
trolls 3x5=8 3150/7=450
28,426
town 300
thugs 500
bandits (A) 4900/7=700
osyluth 6x9 10800/7= 1500
mounds 6x3 3600/7= 500
leshy 6x2 2400/7= 300
3 shamblers 6x3 3600/7= 500
18 skeletons 18x.5 3 cr5=900
6 lg sk horses,4 zombies,
2 imp cr7 1800/7
24 zombies cr9 3600/7
12 lemure(5) osyluth(6)=7 257
8 wights(9) 504
6 ghast (8) 380
6 zombie(5) 128
1 servant(8) 380
6 ghasts 380
2 servants 10 - 760
tamarat 12 1520
8 servants 3040
13 osyluths 750x13 9650
20 skeletons 500
20 zombies 500
bunch of lemure 500ish
8 wight 4000
10th level
bulette cr12 6000
formian warrior 18x3 4500
formian myrmach 10 4500
karnites
tendriculous cr14
shambloids cr4x6
thornmen 24x5
assassin vine 4x8
11th level
aranea cr7x6 4950
worg cr2x6 825
lancers cr6x6 3300
archers cr6x4 2200
dire bufallo 7*8 10,500
gazelle 12 6000
gargoyles
critters
arrowhawks 5750
giants 2xcr12 6000
manticores cr5x2 1026
gargoyles cr10 1500
manticores cr10 1500
umberhulks
traps 5x cr5 750
flesh golems 3200
mimics 2000
chimera 1500
dragon
town 1000
leshy
eagles 300
yrthak 9 1250
hydra cr14 7200
displacer cr 9 1200/7= 170
myreth 69,570
++centipede cr12 3600
hydra cr14 7200
shocker lizard colony ~cr11
6 x2 600
2 x3 300
1x4 900
1x6 450
mudmaw 700
assasin vine 300
12th level
beholder cr13 6600
o'oroth cr11 3300
draconian social 1500
dragons 40000
8 trolls 8hd cr6 ea cr12 82,100
13th level
blevins gap
solanthus Fall Fair, shield g.
Palanthus Inductions-sassanovar
500ea
4 stone giants cr12 2600/6 430ea
ethereal marauder cr9 975
digester cr9 975
4 brown bears (@cr7)
4 wolves(@cr4)
1 wolverine (@cr5) =cr12=2,600
4 ghoul (@cr1)
20 wight (@cr3)=cr11 1,950
hell wyrm cr16 11700
vampire cr13 3900
blue slaad cr14 5850
dinosaur cr14 5850
bulette cr12 2600
goblins cr6 x28 325x28=5850
dire elephant cr13 30hd 3900
dirt tentacles cr13 3900
raiders looters
raiders elite 95,000
pirates 37250/7 =5,300
frost giants 6xcr13 16800
winter wolves 12x~2000
city, investments, wall, sermon 1000
dragons 1000 105,000
ankheg queen cr12 ~cr13
4x ankheg princesses =cr11
ankheg mites ~0xp
4x canonfirs cr12~cr14x4=cr18
tendriculous cr12
spell traps cr14
=15th
negotiations/parley cr16~6000xp
corpse gatherer cr19x3 54000
Thanoi=cr15ish =4500/7=640
4x ice elementals cr15 =
8x frost giant mummies cr14
=3200ea x8 /15 = 1680xp
-16th
remorhaz 4x10 =3300
cr21 dragon
note -combat #90 since 4th lvl
deathbringer cr17 7200
corpse jelly cr19 14400
rav ghoul cr19 14400
elder air elemental cr11 900
elder earth elemental cr11 900
ghaele 13 1600
gelugon 13 1600
vrock 13 1600
42600/8=5510
tower & abyss-gifts 123,510
sylvanesti
blaze 16 4800
squid 16 4800
overland travel
owlbear 15 3200
Karel 10 600
ltouc/vrock 16 4800
ltouc/demons 19 14400 anhkill 21 25600
fiendish occwort 19200
orclingsx12 10800
purple worms cr17 6400
tathar 20 19200
nightshade20 19200
tempest cr16x3 10200
roc cr18 7650
dragon cr18 7650
ruffians cr 19 10200
spell weaver cr19 10200
darktentacles cr19 10200
spell guant cr19 10200
18th level
Ravenous Ghouls
cr21x2 16200x2=32400
cr17x1 3600
cr1 x120 -
[bloodmoon]
Cornugon 15------- 18 1800
marileth 16-- 17/ 2700
nalfeshnee 14 - / 1350
yagnolothx2 15 1800
haamatulax2 11 900
summon traps cr18 5400
medusa-grimlock
assassins cr20 -cr15x6 10,800
imp. Champs cr18x7 37,800
social encounters 1000ea
Publican's day -gael 300 ea
belial cr23 32,400/8=4,000
[Saelek] Black dragon cr17 3600/8=450
19th (excl thrac) 173k
[Saelek] cr16(flee) 1900
brood keeper cr20 8550
swarm cr12x3 700x3
[Saelek] cr16(flee) 1900
devastation giant (geriviar) - cr21 10800
[Saelek] -antimagic field 3rnds
cr23 21600
[goblin horde]
cr3x25 550
cr5x10 440
cr16x6 11400
cr17x2 5700=18090/8=2310
horde 2
cr16x2 7600
cr19x2 10400
18000/8=2250