> from where can I get image file of qnx neutrino 6.5. I want to install it on 
> beaglebone black..??

AFAIK there is no ready-to-use image. That would be too easy, right? You have to build it from the BSP. So download the 
BSP here:

http://community.qnx.com/sf/wiki/do/viewPage/projects.bsp/wiki/TiAm335Beaglebone

and the build it. Good luck!

> from where can I get image file of qnx neutrino 6.5. I want to install it on 
> beaglebone black..??

http://community.qnx.com/sf/frs/do/viewRelease/projects.bsp/frs.texas_instruments_am335_beaglebo.
qnx_650_bsp_beaglebone_1_00_zip

In the zip "bsp-nto650-ti-beaglebone-sp1-trunk-201209071340.zip" there is a folder named images.. There you have an iso 
.ifs "prebuilt-bsp-ti-beaglebone.ifs", it works well.. 

Regards,