Many times, you can subscribe to a service that delievers information to you electronically. Other times, there are no such services available. That does not mean it is illegal to grab this information off the internet. Very often, a government website is required to provide certain information to the public but, they are not required to make it easy for you to obtain this information electronically. This is where screen scraping comes in to play. A program could automatically parse through the various parts of a web page for you and capture and store the data in a database. For some sites, it is easy to write a small utility program to accomplish this. For other sites, we use Mozenda (see: https://www.mozenda.com/).
Mozenda has the tools we need to collect the data you need. It costs a fraction of a cent per penny but, it will save you many dollars of coding time. More importantly, Mozenda has automatic IP switching so that the web server won't block you out if you are retrieving too much information. However, we try and run scrapes automatically in the middle of the night.