Outlook Appointment Contract Printer

I use outlook to put in Rental Appointments for my business to rent sound equipment, like Microphone, PA System, Fog Machine, etc.. When the customer comes to pick up the rental, i look at the info in the appointment and write the info on a pre printed 1 page contract i have. I write in the date, name, phone, price, equipment rented, etc. I would like to have a program i would startup, it would allow me to select and print the contracts with the information in it for that rental Appointment. Im thinking i would want the contract to be extracted from a text file template in case i want to make any changes. Maybe having the data fields indentified by (Name), (Price), etc. I could make a standard for the subject to always be "Rental" as the first word to make it easy to only extract those appointments for processing. So for example it might say "Rental sound system for Mike" in the subject. Then in the appointment box i could put certain info on each line always the same format so the program can know to extract name from first line, equipment on second line, price on third line, date on the 4th line, etc... The program doesnt have to to any calculations or totals or anything...Just insert the data into the contract and allow me to print it.... Currently my contract is just a word document so i dont mind if the program just opens up in word with the prcessed data already to print with a unique file name maybe by date, etc...That way i can make changes if needed. This will be a windows program. I dont really care what it is written in.