Go to Bazur gro-Gharz's house in Cheydinhal, he sleeps about 5am to 6am, kill him when he sleeps and loot his body to gwet unlimited arrows, take them in a quantity of 20 and the game will glitch, so you can get unlimited amount.

A Point of interest, when i did it i put back about 100 arrows and then i could get them in quantity of 100's/200's and soo on and soo forth.

Be careful when trying this cos it might not seem likely but ur emcumberance will increase rapidly.