How do I give a list of sites to Alexa to find data on them?

We don't offer an option to upload a list of sites to alexa.com at this time, however if you'd like to get rank, country, or backlink data for sites you can write a program to read the list and make requests to our Alexa Web Information Service API to get data for each site on your list.

To use the AWIS service you will need to sign up for the service by clicking on the "Sign up for AWIS" button on this page:
http://aws.amazon.com/awis/

The best way to get started is to read the Technical documentation here:
http://docs.amazonwebservices.com/AlexaWebInfoService/latest/

And then modify one of the sample programs here to get the data you are interested in:
http://aws.amazon.com/code/AWIS

The service uses tiered pricing. Pricing information is available on the Sign Up page at http://aws.amazon.com/awis/. Note that API access is not included with an alexa.com subscription plan.