Here is a link to EarthDance’s 2013 Crop Plan Spreadsheet. This document contains a wealth of information! It contains seeding, transplanting, greenhouse and fertilization schedules; budgets; seasonal produce availability; and much more. Make sure you look at the many tabs on the bottom of the sheet.
The University of Missouri Vegetable Growing Calendar is a treasure trove of helpful information. On this site you can find info on 51 different commonly grown crops; when to plant them in different regions in MO; the advantages of particular varieties; and, for some crops, info on everything from row spacing to nutritional facts. Check it out! http://extension.missouri.edu/publications/DisplayPub.aspx?P=G6201
Bowood Farm, a local St. Louis farm business offers many tip sheets for gardeners, including a garden design questionnaire and gardening checklists, both helpful if you are crop planning on a smaller scale. http://www.bowoodfarms.com/index.cfm?fuseaction=tipSheets.main
“How do you grow over 50 different crops for 500 shareholders who are coming to your farm to pick up 13 lbs of vegetables for 24 weeks?” So ask the Farmers of Brookfield Farm near Boston—their answer is spreadsheets! They have a nifty website where they explain a little bit about their process, and also offer you the chance to purchase their guide to spreadsheet making. For $25 they will walk you through the creation of spreadsheets for a crop plan, field plan, field planting schedule, seed order, greenhouse schedule, field record sheet, and harvest records sheet. Whew! http://www.brookfieldfarm.org/CropPlanning.cfm
The Veggie Compass, “an ongoing project of the University of Wisconsin Madison” provides crop planning software in even greater depth. For example, the website explains that using Veggie Compass, a grower can learn if broccoli sales are more lucrative at farmers markets or through wholesale distributors. http://www.veggiecompass.com/
Here is a downloadable pdf. companion planting chart. It allows you to cross-reference different crops to view their compatibility and usefulness as companion plants.
The New Organic Grower by Elliot Coleman. Contains more in-depth information on crop rotation.