i need to crop image in TIFF format. what product i need to buy
Photoshop should be able to handle cropping your TIFF file, possibly Photoshop Elements as well which would cost less. You should get the trial version to make sure rather than buying before trying.
You might also want to check if you already have something on your machine that can do it. On a PC you should be able to right click the image and choose "Open With" whereby a menu of programs should appear with programs that can open the file. You can check to see if any of those listed provide the cropping tool.
If you have further questions you should try posting in the Photoshop forum instead of here (http://forums.adobe.com/community/photoshop?view=discussions). This forum is primarly for questions about downloading and installing Adobe applications.
Try downloading the trial from http://prodesigntools.com/adobe-cs6-direct-download-links.html (Photoshop CS6) or http://prodesigntools.com/photoshop-elements-11-direct-download-links- pse-premiere-pre.html (Photoshop Elements 11).
Make sure you follow the Very Important Instructions before proceeding to the actual download.