My anemometer produces a sine wave output, which could be measured digitally directly into a computer USB port. I attached it to my oscilloscope to see frequency changes, which match wind speed changes. It could also be attached to a frequency counter, like in the higher end digital multi-meters. I also tried recording it as audio and listening directly with a very good quality earphone. The subwoofer sounds were amazing.

I might buy the $10 AVR stick and see if I can write a computer program to convert the data to actual wind speed numbers. I can't find the sample rate for it.
Trouble ALERT: USB 1.1 versus 2.0 issue solved at the bottom of this page:

This Arduino looks better. It has the proper USB jack and C language software for reading accurate analog 5mV increments at high speed as explained here:
It is $29 for the newer version called uno:

or other models:

This PIC microcontroller looked useful as a way of converting the data to mph or kph without a computer:

Here is a great $8 or less transmitter receiver pair to eliminate the telephone wire:

This article about all the different arduino boards was helpful:

Arduino boards are programmed via USB and then they run the program without your computer. So I am not sure if I can
access the wind speed/direction data, while it is being accumulated by the Arduino board. Hmmmm. This needs more research. Edit: I found the answer is YES.
The arduino program has to be set to write to a serial port
and your computer will read that serial port continually.
I will use the method in this link: Arduino + C from this page:

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