Mike wrote:

I'm interested in finding water temperature data for fla****er lakes,
rivers and streams. Does anyone know of an online source?

http://waterdata.usgs.gov/nwis/current

The number of sites with temperature gages is apparently a small
fraction of all US sites. To get started, try clicking "Submit" on the
first page, with no site selection criteria checked.

Once you get to the Available Parameters page, temperature is a
selection under "Water Quality Parameters".

--Dave