EXACTLY where are complete videogame cheats (for single player only!)
avaliable for a disabled veteran who can't play them normally. Is
there a single/best source? I just want inspect  ALL of the game
without the constant repetition. Just shooters for now.

These are my two favorite sources for cheats
http://www.cheatindex.com/
http://megagames.com/
If you have a specific game that you need cheats for and can't find
them, leave a message and I'll see what I can find.

I would go to gamefaqs.com    It is  a complete compository of all
games from the last 20 years.  It includes everything from cheats,
codes, walkthroughs, and messageboards.  Even if a game you play
doesn't have cheats if you register then you can ask other board
members for information.  It really is a valuable asset,  I have been
a member for 4 years now and I can say that it really is a good
resource.

For cheats? Go to cheatcc.com thats a good one.

But I found this while I was looking for cheats

http://www.playstation-game-cheats.net

Its a scientifically proven way to get better at video games.

Check it out. It works great for me.

treat yourself to the new action replay cd for the playstation you get
a cd and memory card for 20 quid ish of the net, place the cd in, load
it, place your game in and it will give you all cheats avalible to
select which one's you want to use. There are 1000's more cheats
avaliable which are not obtainable via a typed code in the games!!!
Have fun

the one gaming site for every consol is

www.gamewinners.com

every cheat that i have gotten off of it has been correct and not false.

i find it very usefull to help me out they have the following gaming consols

CONSOLES  
     3DO Multiplayer
     Atari 2600
     Atari 5200
     Atari 7800
     CD32
     CD-i
     ColecoVision
     Dreamcast
     Gamecube
     Genesis... Megadrive...
     Intellivision
     Jaguar... Jaguar CD...
     Master System
     NEC PC-FX
     Neo*Geo
     Neo*Geo CD... Neo*Geo CDZ...
     NES... Famicom...
     Nintendo 64... iQue... 
     PlayStation... PSone... 
     PlayStation2
     Saturn
     Sega 32X
     Sega CD... MegaCD... X'Eye... WonderMega...
     SNES... Super Famicom...
     TurboDuo... Turbo CD... PC Engine CD...
     TurboGrafx 16
     Vectrex
     Xbox
     Xbox 360
 
 


COMPUTERS  
     Amiga
     Apple II... Apple IIe... Apple IIgs...
     Atari 540ST... Atari 1040ST...
     Commodore 64... Commodore 128...
     DOS/Windows PC
     Macintosh
 
 


PORTABLES  
     DS
     Game Boy... Game Boy Pocket...
     Game Boy Advance
     Game Boy Color
     Game Boy e-Reader
     Game Gear
     Game.Com... Game.Com Pocket Pro...
     Lynx
     Neo*Geo Pocket... Neo*Geo Pocket Color...
     Nomad
     PSP
     TurboExpress
     Virtual Boy
     WonderSwan
     WonderSwan Color
 
 


OTHER  
     Arcade
     DVD Video
     DVD Player Multi-region
     Handheld Games
     N-Gage... N-Gage QD
 
 

now if this isn a cheat website then i dont know what is.....
they also have 

videos
reviews
trailors and everything

hmm, there are too many good sites actually let me try to list them here.

http://gamecheats.eu/
http://www.gamefaqs.com/
http://www.megagames.com/
http://cheatcc.com/
http://www.cheats.ign.com/

hopefully you can find all cheats down here.