Could anyone tell me any website from which I can buy a U-lock holder. I need to attach it to my frame so that it doesn't scratch the bike. Already tried performancebike and nashbar with no luck.

thanks

I would call the manufacturer and ask for one. Personally I have never had luck with any u-lock holders.

TwoFish products have received decent reviews: https://www.twofish.biz/bike.html

Online retailers list on this page (some links appear to be dead): https://www.twofish.biz/bikes_retail.htm

+1. Manufacturers often make a frame mount for their U-locks, though I also agree that I don't care for them. They take up too much space inside the frame. My favorite u-lock "mount" is a rear bike rack with tie-downs to tie the u-lock to the rack.