Finding you SteamID is something that is really easy to do. Follow the steps listed below and you will have your SteamID in no time.

• Launch any multiplayer game such as CSS or TF2
• Join any online server
• Open the console (If you do not have this enabled, go to Options>Keyboard>Advanced and click Enable developer console, then submit the changes)
• Type status in console
• Find you name in the list and copy that line
• Paste the line with your name in it in any text editor
• Find the part after your name that starts with STEAM_ (EX. STEAM_0:0:1)
• You now have your SteamID