can i use web crawler to find a specific information from thousands of webpages

i am not a web expert less web coding but more of a low level developer. i am considering the web portal online database startup and one of the pressing issue is can i use the web crawler to pull specific information intelligently from a thousands of web page: examples are: building a database of 10-Q, 10-k report of thousands of companies. So web crawler visits each company page and find that information and pulls it and integrates into database.

I am not asking for specific code or examples, so question is whether this is possibility at all using web crawler or something else. If so, what are the approach? Any ready library, plug-in? language to be used? Thanks!