programming atmega 8

i need a suitable usb programmer for atmega 8. can any one send me the circuit diagram and boot loader. im new to arduino pls help

One of the Arduino compatible versions is Arduino NG with ATmega8 with an external X-tal at 16MHz.
That is not the ATmega8L at 8MHz.

So the easiest way is to use the ATmega8, and add a 16MHz X-tal with two 22pf capacitors.
The Arduino IDE can upload the bootloader (it will also set the appropriate fuses when uploading the bootloader).

You will need a programmer. An Arduino board can be used as programmer (Arduino as ISP) or you can buy a USBasp programmer.

Take a look at these pages:

http://playground.arduino.cc/Learning/AtmegaStandalone

thanks for your reply, where to get sample programs for atmega 8 and boot loader for it

Most examples in the Arduino IDE (the Arduino software on the PC) will work.
The bootloader is in the Arduino IDE. You have to select the programmer, and burn the bootloader. It is all done from within the Arduino IDE.

Why not just burn in the Optiboot bootloader from the beginning? it takes less space (512b), faster baud rate for uploading and it doesn't have this really loooong delay before the code starts running.