Go to your steam directory/Steamapps/Your username/sourcesdk/bin/source2007/bin
Then you should find a file called GameConfig.txt, Open this up, And paste the following. If the file does not exist, Create it, And don't forget to replace your username at a few places, As well as changing the directory if it is incorrect for you, These are the default directories for an installation on a C: drive with a x64 OS.
"Configs"
{
"Games"
{
"Goldeneye: Source"
{
"GameDir" "c:\program files (x86)\steam\steamapps\sourcemods\gesource"
"hammer"
{
"GameData0" "c:\program files (x86)\steam\steamapps\sourcemods\gesource\goldeneye.fgd"
"GameData1" "c:\program files (x86)\steam\steamapps\USERNAMEHERE\sourcesdk\bin\source2007\bin\base.fgd"
"TextureFormat" "5"
"MapFormat" "4"
"DefaultTextureScale" "0.100000"
"DefaultLightmapScale" "16"
"GameExe" "c:\program files (x86)\steam\steamapps\USERNAMEHERE\Source SDK Base 2007\hl2.exe"
"DefaultSolidEntity" "func_detail"
"DefaultPointEntity" "ai_speechfilter"
"BSP" "c:\program files (x86)\steam\steamapps\USERNAMEHERE\sourcesdk\bin\source2007\bin\vbsp.exe"
"Vis" "c:\program files (x86)\steam\steamapps\USERNAMEHERE\sourcesdk\bin\source2007\bin\vvis.exe"
"Light" "c:\program files (x86)\steam\steamapps\USERNAMEHERE\sourcesdk\bin\source2007\bin\vrad.exe"
"GameExeDir" "c:\program files (x86)\steam\steamapps\USERNAMEHERE\Source SDK Base 2007"
"MapDir" "c:\program files (x86)\steam\steamapps\sourcemods\sourcesdk_content\gesource\mapsrc"
"BSPDir" "c:\program files (x86)\steam\steamapps\sourcemods\gesource\maps"
"CordonTexture" "tools\toolsskybox"
"MaterialExcludeCount" "0"
}
}
}
"SDKVersion" "3"
}
Then start up Source SDK and you should have Goldeneye Source in your configuration list for Source Engine 2007.
Hope that helps!