I while back I was thinking to create a few fictitious pilots and I needed call signs for them. Since none of us can die in the Battlestar Universe, I planned to have a few of the make believe pilots bumped off by the Cylons during each mission to add an extra touch of realism. I did a bit of searching online and I came across this web site: http://www.f-16.net/callsigns-E.html
This web site has call signs used by the USAF listed from "A" to "Z." There are 125 pages to read through and thankfully you can click on what ever letter you want to see the call signs beginning with that letter.
I know most of us already have a call sign and I guess this site would be best used by new pilots. If you have the time and want a good laugh, read some of the stories behind the many call signs to learn how the pilots earned their call sign.
We have it easy because we can choose whatever we like. It's not done that way in real life. Pilots are given a call sign that has to do with their mistakes or undesirable personal quirks.
BTW, my call sign was a nick name given to me by one of my younger brothers friends. He though it would upset me. Little did he know that I thought of it as being funny and I didn't mind it at all. In a short time everyone was calling me Reamer and its stuck with me for many years.