The Glebelands-Unicorn Model: an article about Glebelands from Unicorn website
Unicorn's own website
Glebelands City Growers - new producers on Sale site
Growing - technical information
The Organic Growers Alliance website, complete with a forum for discussion around commercial horticulture, various technical articles and magazine, of interest to all growers, commercial and home
Vegetable growing information also available from from Garden Organic (formerly HDRA) Organic Vegetable Systems studies- case studies/weed control/machinery/varieties/etc
Technical information also on Soil Association site, including factsheets
The Rodale Institute in the US, the New Farm's inspiring site with a newletter and plenty of postitive info on organic farming in the US and worldwide
The National Sustainable Agriculture Information Service (ATTRA), also from the US, has loads of downloadable technical information
Although certainly not organic, the Irish Agriculture Development Authority has some useful info, and they have other useful factsheets too,https://www.teagasc.ie/crops/horticulture/vegetables/vegetable-publication
See the weekly newsletter from https://wickedleeks.riverford.co.uk/author/guy-singh-watson for horticultural commercial realities and up to date field news
For reference, anything by Joy Larkcom, especially Grow Your Own Vegetables (Frances Lincoln) - no glossy photos, just lots of invaluable advice on planning/sowing dates/harvesting/watering etc for a range of vegetables, all packed into one very reasonably priced paperback.
Also see Eliot Coleman: books, especially The New Organic Grower and http://fourseasonfarm.com/: theory on growing, freshness and eco-ness of it all.
It is important to keep referring back to the principles behind organic agriculture and horticulture - for example to forestall any attempts to "water down" standards or deal with potentially woolly ideas about substituting ill-defined words like "sustainable" for "organic". Albert Howard was one of the most important founders of the organic movement.
LBS (Mail order catalogue). Huge range of equipment.
Agralan (mail order). Fleece/mesh.
Plant Nursery Delfland
See the End of Suburbia (DVD) for some scary realism about oil (we're running out of it fast).
A positive documentary about a post oil future: https://shop.cuba-solidarity.org.uk/departments/films/306/dvd:-doc:-power-of-community,-the-:-how-cuba-survived-peak-oil (DVD)
Sustain - the Alliance for Better Food and Farming - website/reports/campaigns. See particularly their seminal report on oil and food, Eating Oil
https://en.wikipedia.org/wiki/Jared_Diamond (books).”Collapse” despite unfortunate title seminal work.
"Empires of Food" Evan Fraser and Andrew Rimas. Taking up some Jared Diamond thinking but adding, concisely, a lot more history. Great on Fritz Harber(-Bosch), Rome and living off the family silver.
Food Security in Britain - a Soil Association report
Some writers and commentators:
Kevin Anderson(Tyndall Centre, Manchester). Climate change expert, even if lots of people don't want to hear what he has to say! https://twitter.com/kevinclimate?lang=en
The Food Programme (Radio 4): Sometimes very on track, bring on the new Derick Cooper!
wwoof - work on organic farms and smallholdings in exchange for food, accommodation and learning opportunities...(but don't go by plane...)
helpex - includes opportunities to volunteer on organic farms etc (but not by plane!)