Software-Linux

• O'reilly guitar software review
• LinuxLinks.com: List of guitar software.
• JACK RACK: Guitar effects software for Linux - uses LADSPA plugins.
• RAKARRACK: Guitar effects software for Linux.
• Rakarrack again
• Gentoo guide RACK installation
• JACK: List of SW using JACK on Linux.
• ExEf: The "Extreme Effects" sound processor.
• guitarx: Good-looking effects processor.
• JESUSONIC: Effects processor running in the console.
• Sound & MIDI SW 4 linux: A nice list of audio SW for Linux.

Software-Windows

• Guitar.FX: Guitar effects software for Windows.
• REAPER: Digital audio workstation for Windows
• Guitar Rig: An amp and effect processor.

General

• thomann: A good shop - fast international delivery.
• Blues sound informations
• GuitarBackingTrack: Audio tracks (inkl. mp3) without guitar track.
• midi-tab: MIDI audio tracks.
• ultimateGuitar: Tablature for a looooot of of songs.
• Easy songs
• The guitar players toolbox - easy songs
• DBZ Guitars
• thomann: A good german shop - all kind of instruments.
• Rocksmith: A music game to be played with your a real electric guitar!