This is a compilation of every skin available on the M3 Sakura FAQ.  This skin pack does not include all the available wallpapers, only the skins.  You may find wallpapers at the following URLs:
http://www.megaupload.com/?d=NAJ2XHOZ
http://gbatemp.net/index.php?showtopic=137545

Please do not alter the contents of this archive.  Do not unpack, delete all the readme files, sound effects, source files, etc., then repack just the skins and redistribute them, as it goes against the wishes of several of the skin creators.  Please respect their wishes to keep their skin archives intact.  You may alter the contents of this archive any way you want for your personal use only.  

This skin archive is from the M3 Sakura FAQ at GBAtemp.net: 
http://bit.ly/M3Sakura

22 December, 2009
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M3 Sakura Skin Index
===================================
[2461]default - gangsterboi
[2568]Sakura_DS_OS_0.8 - wabsta
[2575]Paradise - strata8
[2580]M3_Vista - gangsterboi
[2598]ChaosBlack - Chaos45
[2605]Exultation_v2 - Geo411m
[2630]MoonlightWhite - Chaos45
[2708]Sakura_Aero_1.2 - strata8
[2740]Aero___Fish_School - strata8
[2747]Aero___Ultimate - strata8
[2823]Sakura_GITS - EeeKay
[2831]area_o4.2 - strata8
[2942]Sakura_GITSDark - EeeKay
[3008]Sakura_Clearlooks - strata8
[3084]Sakuratronic_Final - Toni Plutonij
[3216]Death_Magnetic_Sakura_V1.0 - metalliguy
[3238]lulzpirate -  RyukeDragon
[3246]Smash_Bros_Brawl_Sakura_V1.0 - metalliguy
[3262]Midniight_Flower_M3_Sakura - metron
[3270]Sakura_Wolf - metron
[3271]Black_NDS_Firmware - metron
[3314]White_NDS_Firmware - metron
[3328]Pokemon_Master - metron
[3341]tragedy099 - RyukeDragon
[3357]DD__Dawn - metron
[3362]shadow4.67 - lilkerv90210
[3420]Princess_of_Hoenn_V2 - metron
[3421]Tomboyish_Mermaid - metron
[3422]Pokemon_Platinum - metron
[3478]Mother_3 - metron
[3542]Mother__Earthbound - metron
[3733]Blue_Fluff - metron
[3931]Sakura_Dark_Beam_V1.2 - metron
[3948]DontPanicMarvin - VatoLoco
[3968]SAKURAtemp - metron
[4201]GBS.zip - metron
[4367]AAA - darknick
[4549]PSPsakuraskin - metron
[4656]Wii - metron
[4908]Moonshell_BETA_2_5 - metron
[4930]Vista_Rus_1.34 (Russian) - mc_B3oWoLF
[4950]M3Sakura_Moonshell - metron & dohclude
[4951]default_green - dylan2228
[4959]VistaStyle___Grass - Axel-MaV
[4960]VistaStyle___Aurora - Axel-MaV
[4961]Sakura_Black_and_White - dohclude
[4992]PM3Sakura - Mathias Mahling & Lathlas
[4993]Doki_Doki_Majo_Shinpan - metron
[5009]Ubuntu_Sakura - powered_by_tux
[5085]Sakura_DSOne_Ver1.0 - KH-Roms
[5423]MadiColor - metron
[5776]E_NSakura - gangsterboi
[5818]_Skin__M3Sakura_Faith (Spanish) - Nagaroth
[5901]Fade_Away - metron
[6411]Floral_Attentive - DesuChan
[6412]RevenG - DesuChan - 
[7126]BlackAndRed - Magmorph
[8737]-GOW - KingVamp
[8870]-gta4 - KingVamp
[8985]-Castlevania Sakura Skin - Dark Justice
[9057]-Pure Sakura - Jaylen
M3Sakura_Ver110_Aqua.skn - M3 Sakura
M3Sakura_Ver110_Buccaneer.skn - M3 Sakura
M3Sakura_Ver110_Dashboard.skn - M3 Sakura
M3Sakura_Ver110_Default.skn - M3 Sakura
M3Sakura_Ver110_SakuraBlue.skn - M3 Sakura
M3Sakura_Ver110_SIMPLE.skn - M3 Sakura
VistaDX_1.1f - Aphexdash