Market Stall Trader and Bookkeeping (Starting-Up)?

I'm starting up business as a sole-trader. Will sell at car boots, flea markets, and so on. I have personal experience; enough to make it financially worthwhile. For my own purposes, I'm having trouble identifying/ obtaining the necessary single-entry bookkeeping spreadsheets needed. If anyone presently is a market stall trader or starting up (similar to my own position) can they please recommend a site which provides ''free'' small business spreadsheets. The spreadsheets I'm exclusively interested in, ought relate to a business that has limited receipts given the domestic, mobile, and public nature of (purchases and retail) car boots and flea markets. I'm assuming I do not need double-entry books as there will be no creditors, debtors, invoices and so on. The little detail I've accounted for to date includes a petrol mileage log, both a business and personal cashflow analysis spreadsheet, a trading and profit and loss account and other spreadsheet templates which illustrates my ignorance so far. Lists of bookkeeping sheets might help, but I assume a like minded minded business individual, retired or otherwise, will know which books I vaiguely make reference to. If indeed, spreadsheets need be kept. Thanks to any response in advance. Sorry for the long-winded background infos. Hope this helps. Please help.