Questions about temperature

I just vary the height of the heat lamp over the brooder.  If you need hotter lower the lamp, if you need cooler raise the lamp.  The other thing I've done is mounted the lamp off of a work bench and then raised or lowered the brooder using blocks of wood.  It's helpful to have a small thermometer in the brooder so you can watch temps.

Put it at chick level.  I usually just put a small block of wood on top of the bedding and put the thermometer on that.  It doesn't need to be directly under the lamp, just within the where the heat is.  Also don't get too wrapped up in watching the temps, use it just to prevent going to the extremes of high and low temps.  If your chicks are staying at the opposite end of the brooder then it's too hot, if they're huddling under the lamp they might be a little cool.

You want an infrared heat lamp in a reflector.  Here's link to the heat lamp at Mypetchicken.com and on the same page they list the reflector.

http://www.mypetchicken.com/catalog/chickens/Infrared-Heat-Lamp-Bulb-White-Energy-Saver-p967.aspx

Or, you can buy a Brinsea Ecoglow heating unit and forget the heat lamp completely.  Not sure if you could find it locally though.  You'd probably have to order it online.  The heat lamp and reflector is inexpensive and any farm supply/feed store should have them in stock.

http://www.amazon.com/Avianweb-EcoGlow-20-Chick-Brooder/dp/B0051ZG3R8/ref=pd_sim_sbs_petsupplies_1

i always used a drop light with a 60 watt bulb in it to keep the chicks warm.an i never had cold chicks doing that.

How much heat you will need will vary depending upon many factors.  Thing such as the size of the brooder, the type of material it is made of, etc will influence it.  A brooder in a sunroom is going to be a challange to keep the temperature steady.  I setup my brooder in the garage (it is insulated and built into the house) where the temperature is pretty consistent.