The T3i, like all digital cameras, utilize a preflash metering method for automatic adjustment of the built in or dedicated external speedlite. To my knowlege, the Rebel series cameras do not allow the preflash to be defeated, similar to most other sub-$1000 cameras, nor do the same provide a PC terminal for studio flash. Additionally, the wireless commander built into any camera is geared for wireless automatic flash. This uses a series of flash commands before exposure to set the appropriate levels. There is no effective way to use the wireless commander of your camera with the Alien Bees or other studio lights (there are ways, but there are better means of triggering).
The most cost effective route would be to use a hotshoe adapter to allow the sync cord included with the lights to attach to the camera. These run in the $15 range, and are available through us, or through most camera stores:
http://www.paulcbuff.com/hsa.php Generally regarded as a better way is to use a radio remote system. We offer a system known as CyberSync. Radio remotes both eliminate teh long wires as well as by pass the easily defeated optical triggering methods.
http://www.paulcbuff.com/cybersync.php In the interim, but not recommended for long term use, you can use the FEL (flash exposure lock) feature of your camera. If I recall correctly, the asterik button, when pressed, will fire the preflash. This will allow enough time for the Bee to recycle for the actual exposure flash. If the option exists, I would have FEL set to toggle and not hold. This means you press the button to activate, and again to deactivate. This is opposed to hold, which means it is only active as long as the "*" button is depressed.
Alternatively, if you have a speedlite with manual control, you can set it to manual and dail the power as low as it can go. This will both eliminate the preflash as well as not impact the image with its own flash contribution. If you can tilt or swivel the head of the speedlite, doing so can contribute even less to the scene.