Decided to collect all the numbers scattered through multiple threads here. Please post additional part numbers, corrections, and requests in
Info And Part #'s For The Ls2 
LS2 Part Numbers
LS2 bare block = 12568950
LS2 crate motor = 19156261 (formerly 12499750)
LS2 longblock assembly = 89017654
LS2 camshaft = 12574519
LS2 timing chain = 12586482
LSx lifter = 17122490
LS2 front cover = 12600325
LS2 rear cover (same as LS1/LS6) = 12572014
LS2 90mm throttle body with actuator (same as LS7) = 12570790
LS2 throttle body attachment fastener x4 = 11519971
LS2 throttle body attachment seal = 12576549
LS2 MAP sensor = 16212460
LS2 intake manifold = 89017648 or 12589181
LS2 intake to cylinder head gasket x8 = 12580833
LS2 intake manifold attachment bolt x10 = 12552344
LS2 intake manifold sight shield, LH = 12568998
LS2 intake manifold sight shield, RH = 12569246
LS2/LS7 valley cover = 12570471
LS2 fuel injector assembly x8 = 12569113
LS2 fuel injector o-rings (orange) = 89017587
LS2 fuel injector retainer clip x8 = 24503227
LS2 fuel rail = 12572174
LS2 fuel rail attachment bolt x4 = 12590276
LS2 front coolant tube = 12578838
LS2 rear coolant plugs x2 = 12563325
LS2 polished rear wheel = 9594349
LS2 valve springs (same as LS6) = 12586484
LS2 valve pushrod cover guide (lifter tray) = 12595365
LS2 cylinder heads (same as LS6) = 12564825
LS2 cylinder intake valve (same as LS1) = 12563063
LS2 water pump = 89017457
2005 Corvette C6 LS2 exhaust manifold, LH = 12569388
2005 Corvette C6 LS2 exhaust manifold, RH = 12576061
2004-05 GTO LS1/LS2 exhaust manifold, LH = 12563277
2004-05 GTO LS1/LS2 exhaust manifold, RH = 12563278
2003-05 SSR LH6/LS2 exhaust manifold, LH = 12567483
2003-05 SSR LH6/LS2 exhaust manifold, RH = 12567484
C6 LS2 oil pan (has shallow rear sump) (kit with bolts/gasket) = 12581810
C6 LS2 oil pick-up screen (same used on LS6) = 12558750
C6 LS2 oil deflector (same as used on LS6/LS1) = 12558189
C6 LS2 dipstick = 12570788
C6 LS2 dipstick tube = 12570787
SSR/Trailblazer 5.3L/LS2 oil pan (has front sump with hole for 4wd front axle) = 12579723
GTO LS1/LS2 oil pan (has front sump) = 12581209
2005 GTO LS2 PCM = 92180030
2005 GTO LS2 ECM = 12597883
LS2/LS7 spark plug wires = 89018058
LS2 flywheel = 12571611
Sources:
Info And Part #'s For The Ls2 LS2 Block Part Number LS2 TB's at SDPC!! LS1 to LS2 intake swap (f-body) part numbers LS2 new? carte motor gmpartsdirect.com selling LS2 parts soon? ls2 exhaust manafolds Part # for the LS2 block? Anyone interested in LS2 part #s? LS2 Part Numbers Needed LS7 plug wires LS2 PCM part# Part # for LS2 fron/rear covers?? Anyone know the part number for the LS2 valley cover...
LS2 and LS7 GM Parts Numbers List 
