You'll be very happy you change to using a scale!
http://www.cookscountry.com/ did a review of inexpensive instant read
thermometers and found a real winner...but I'm not a member. Go
there and get a free 14-day trial and you can read the review.
If you want to spend $90 get the Thermopen thermometer...the one
above costs under $15.
I'm no scale expert (I think Mike Avery is, if he wants to chime in
here). I've gotten fine results using a Salter scale (about $40 after
discounts). I've also heard some enthusiasm for the smaller MyWeigh
scales (see them online).
Whatever you get, just make sure the one you get has about a 10-11
pound capacity, not 4 pounds. That way you can put your mixing bowl
right on the scale and add flour to it. 1/8th ounce accuracy is fine.
Allen Cohn
SHB
San Francisco