Manufactures Information Pages

these are useful links to information like product datasheets, user manuals and guides, downloads, technical data and drawings etc. on old and new equipment. These links although in the public domain of the site are mostly hidden away and or take multiple clicks to find them.
      
Shure - Datersheets etc.
http://www.shure.com

Turbosound - .dwg drawings, Datasheets, Photos, Manuals etc. (ftp. site, so text only till you get to the .pdf, .jpg  you want)    
www.turbosound.com/

Soundcraft - Manuals, Datasheets, etc. http://www.soundcraft.com/downloads/user_guides.aspx?pid=1

QSC - User Manuals
http://www.qsc.com

Links - Software
Audio, Video

Audacity is free (to use) open source software for editing and recording sound
https://www.audacityteam.org/ 

Mixxx integrates the tools DJs need to perform creative live mixes with digital music files.
Whether you are a new DJ with just a laptop or an experienced turntablist, Mixxx can support your style and techniques of mixing.
https://mixxx.org/

Wave Editor is a fast and easy digital audio editing software for Windows. It provides a powerful and user-friendly editing environment that is especially suitable for beginners, it can perform basic editing functions like cut, copy, paste and delete parts of recording.
http://www.wave-editor.com/

LMMS (Linux MultiMedia Studio) is a free cross-platform alternative to commercial programs, which allow you to produce music with your computer.
https://lmms.io/

FreeRIP is an advanced CD to MP3 Converter that comes packed with features. It can also convert MP3 and other audio files from one format to another. For example FreeRIP can convert audio files from WMA to MP3, or OGG to MP3, FLAC to MP3 or WAV to FLAC etc.
http://www.freerip.com/

Avidemux is a free video editor designed for simple cutting, filtering and encoding tasks. It supports many file types, including AVI, DVD compatible MPEG files, MP4 and ASF, using a variety of codecs. Tasks can be automated using projects, job queue and powerful scripting capabilities.
https://avidemux.sourceforge.net/

VLC media player is a free and open source cross-platform multimedia player and framework that plays most multimedia files as well as DVD, Audio CD, VCD, and various streaming protocols, it also has some useful features not found in other media players like the ability to Record.
www.videolan.org

OtsAV is a PC-based professional digital media playout system for the Windows platform used by DJs, broadcasters, venues & music or video solution providers. With first-class automation and full manual control, OtsAV is the premier DJ software in popular use since 1999.
https://otsav.ots7.com/

DMX lighting control these types of software will require a handwear interface - USB, RS232 or Network (Cat5) to 5 or 3 pin XLR - there is normally a cost involved ether from the software provider or in buying third-party handwear.

Freestyler is free lighting control software used by many leading dj's, venues and lighting designers and supported by a vast network of users worldwide
http://freestylerdmx.be/

Q Light Controller is a cross-platform application for controlling DMX or analog lighting systems like moving heads, dimmers, scanners etc.
www.qlcplus.org

Links - Software
Other

OpenOffice is the leading open-source office software suite for word processing, spreadsheets, presentations, graphics, databases and more. It stores all your data in an international open standard format and can also read and write files from other common office software packages.
http://www.openoffice.org/

AVG antivirus the world's most downloaded free security software, basic protection for surfing, searching and social networking
http://free.avg.com/

GIMP is the GNU Image Manipulation Program. Software for such tasks as photo retouching, image composition and image authoring.
http://www.gimp.org/

there is also a list of free and open source software packages can be found on Wikipedia, the free encyclopedia
http://en.wikipedia.org/wiki/List_of_open_source_software_packages

Links - Trade Associations

PLASA (Professional Lighting and Sound Association) www.plasa.org

PRS for Music (Copyright Protection Company) www.prsformusic.com

Musicians' Union  www.musiciansunion.org.uk