Messing up my Templates

While killing the time trying to determine if I'll buy or not, I browsed through other people's blogs. Then I came across the site Blogger Templates. I liked one template there and tried to use it on my site. However, there were some problems in it that I had to revert back to my old Template. And guess what, all of my right side gadgets disappeared except for the labels and links. Do I have to repeat doing this every time I change templates? This is so frea*** frustrating!