I'm hoping this presentation about cashflow should work
http://tutor2u.net/business/presentations/accounts/cash_management/index.html#
If it doesn't, try this one:
http://www.bized.co.uk/learn/business/accounting/cashflow/simulation/index.htm
Then have a look at working capital:
http://tutor2u.net/business/finance/workingcapital_needs.htm
