View Avr Isp Programmer Schematic Pics. It is chinese version with pl2303(usb to serial). You can find a lot of cheap or expensive isp.
This programmer will work with a wide variety of atmel avr and at89sxx microcontroller.
You can find a lot of cheap or expensive isp. The biggest complication is always the burning of the bootloader. Open a simple blinking led example and adjust the pin values according to the schematic of your device. Usb avr and at89sxx isp programmer is low cost usb based programmer.