I think any software will do really. A procedure could take the form of written text, processflows, pictures, television (used for promotion of gadgets in supermarkets). Though, my advice would be to use software that will work through many years of updates, ex MSOffice etc.
I have choosen to use MSWord and Excel for writing and for pictures. Visio for graphic process flow descriptions - it's easy to paste into word and you can add comments and resposibility by dividing your word document into 3 columns.
We use MS Sharepoint to mange our document system. The advantages is that it is easy to use and works without any problems together with MSOffice2000 (not really with older versions) and it is very very cheap compared to other document control systems (about 1/20th of the cost).
The best system will only have pictures, symbols and graphic process flows with reference to result documents. A good rule is that any procedure should fit on 1 A4 and the fontsize shouldn't bve less than arial 10

. If you manage this, I think the procedures even might be read and understood.
Fredrik