I almost always plug my laptop in for power. How can I extend the life of the battery ? Can I remove it when I plug it into the wall?

The best way to do it is to let the battery charge to full power without using it, and when it is done, unplug the cord. Use the computer until the battery power is completely gone, every time. Make sure you save your work constantly though, so you don't wait until it's too late. Most laptops do work without a battery installed, but I will have to have the make and model of it to tell you for sure. Or you could just take it out and see!

I do not recommend running the laptop primarily on battery.

Depending on the type of battery you have, if you run it down a little bit each time, then recharge it, you might be causing the battery to conk out after a short time. So I would run it down completely, then recharge it and afterwards, pull the battery when you connect it to AC.