Salesforce integration with MS Access database

We maintain a MS Access database for tracking complete company payroll information. This includes employee names and addresses, direct deposit information, pay rate(s), deduction(s), benefit(s), time off accrual, and taxes. We would like to export data from MS Access to SF each pay period with current pay amounts and allocation of expenses, then import any changes in data from SF to MS Access before we calculate payroll each week. We have considered dumping our MS Access tables to database.com each pay period and connecting database.com to SF - then overwriting the MS Access tables each pay period before running payroll. There must be other options. Please contact me with any questions or concerns. I'd like to begin the project ASAP.