Hi Hsu, I am living in Xian, but I don't know where to find an English guide, except for asking the travel agent for help. 3 days is enough to explore Xian. Actually you can finish the highlight sites in Xian within 2 days. Of course the terracotta warriors museum is a must see thing. I recommend you to visit the Tang Dynasty Palace which is a newly built garden imitating the buildings in Tang dynasty. Hope you can like it. OH, welcome to Xian. :)