Finger print sensor are available form ATMEL , Fijus , ST, some korean manu .
Theses are varoius type like optical, thermal , capacitive type. These are easily available from varoius electronics compoment supplier.

Interfacing these sensor module is a tough task as there output are in parallel bus or SPI interface which requires reading each sensor pixel & processing it. Generally it requires 32 bit microcontroller with DSP capa. Apart from this finger template processing , extrctiion , storage & matching etc requires very complex mathematical algorithem available through very hihh priced licensing only(source code).

But now a days sensor manufactures also gives you complete embedded module where burnt embedded firmware performs all thess task for you. These modules now a dayds using ARM proesssor. Output of these modules for interfacing to your application is available as RS-232 of USB.

I have got one such module. If you are interest I can sell it to you