How to charge an extra cell phone battery?

I'm getting my 1st cell phone in a couple months and I've got my eye on a phone that doesn't have that great of a talk time(RIM Blackberry Pearl 8100). So I was planning on getting an extra/spare battery; but I don't really know how I would charge it separately without having to insert it into my phone and then charge the whole phone. Can anyone explain how I would do this?

You can't. Not without putting it in the phone. Just choose a phone with better talk time. I have a Pearl. It might not have the best talk time, but the standby time is pretty good.

Another truth for you is it would be cheaper to just get car charger or another wall charger. An extra\replacement battery is pretty expensive.

You will need to order a charger that you put the batterys in it rather then into the phone.

Hard to describe, take a look at this for a better idea on what I mean

http://store.bbnauts.com/blackberry-mini-external-battery-charger/5A83A3303.htm