converting a amount displayed in textbox(float value) to string( c# 2008,SQL SERVER 2005)

I am working on a desktop application.Its a billing software.I have written code for calculating total bill and displaying it in lable.Now what I want is to convert that value to string and display it in another textbox.(for eg total bill is 2707.12 and It is displayed in label ,I want to display amount In words in textbox as Two Thousand Seven Hundred Seven & Twelve Paise)how To do? Thanks for your time and consideration.Looking for favorable reply soon.