I first spent around US $25 for a cheaper-than-cheap tripod from Meijer,
while I still had only a PowerShot camera. With a creaky and lousy pan/tilt head,
it was relegated to the trash pile within weeks.
Next was a Manfrotto 725B DIGI. US $95(discontinued).
I love this tripod, and it's a great economy tripod. No more droop and faltering
adjustments, and it's a great tripod for the price. I managed to upgrade the center
column/head assembly to accept standard heads for only US $40, and put an Amvona
clone of the 486RC2 head on it. I still use it when I want light weight and portability.
There's a current replacement to this setup, and I'm sure someone else will chime in
with information about it.
Last, I decided to bite the bullet and get a 'real' setup: Manfrotto 055XPROB legs
with a Manfrotto 488RC2 ballhead. Super-secure rig, and it's almost as stable as
granite. Spent US $244 for the pair.
There are better choices of heads to be had now, as many will recommend the newer
498 over the 488, but the cost averages out to be around the same.
Make your choice:
If you want super-rigid performance, prepare to spend a good amount.
If you want passable and decent performance, go mid-level on price.
If you want to experiment, then keep spending $100 until you arrive at something
which suits your fancy, most likely well and beyond your first few expenditures
of $100.