As chair of Eynsham Allotment Association (Oxon) I created my own spreadsheet to manage my allotment site which has around 150 plots. It includes the following sheets:
PeopleTbl - comprehensive table for each person associated with the allotments. This is the main table. It includes all personal details, what plot(s) they have, what rents they are charged.
PlotTbl - Full plot details, includes size of each plot. The size is coded to link with RentTbl
RentTbl - the basis for charging depending on plot size and concessions, eg retired.
PlotMap - A spreadsheet map of the site. This is the key to the whole thing. This sheet comes in various incarnations, eg
MapNames - Same design as PlotMap but showing the plotholders for each plot.
Cards - A visual form of PeopleTbl used for plotholders to update their own details.
There are other sheets that help a chair have an oversight of the allotments. For instance it has a water table with the usage going back over time. Also there is a list of external contacts, local orgs etc. It also has the key figures from annual accounts so we know the history of the money.
The whole thing is very automated. It can help deal with issues such as plots being merged or split. It can answer questions such as if we raise the rent by £5 then how will that affect our bank balance.
Oh, and because it runs on GoogleDocs it is live to all committee members.
If any chairperson or secretary is interested in this I can work with them to clone my spreadsheet for their use. Anyone taking it on would probably need some spreadsheet skills. If it works for you then I would expect a donation to a charity -
www.sudep.org.