FREE Date Picker
When you ask your visitor to fill in a date, or a range of dates, and give them some format to fill in (i.e. mm/dd/yyy) they will probably leave your web. It became quickly an industry standard to provide them with a pop up little calendar where they can pic the date just by clicking on it. But don't worry - you don't need to re-invent the wheel here - others have done it for you already. The following is a link (courtesy of Kelvin Luck)
to several scripts, that you can easily implement and have a nice date picker on your web: