rear speakers set-up for 5.1 audio

For those that have 5.1 speakers for PC, how do you set-up your rear speakers? Did you buy speaker stands for them?

I don't have anywhere behind me to put mine, so my right one is on a bookshelf to the side, and my left one is down low on the sub. Not the best set up. Up in my room I just used my dresser and bookshelf which were at about the same height.