Web crawler/spider

I am looking for an expert on web crawling, to help;

- Advise on the what is possible with Web crawling.
- Estimate size and scope of my potential project.
- Suggest he most cost effective way to implement, own server Vs hosted solution.
- Help implement solution.

I am keen to search all public websites for email addresses, capturing
- The email address
- A link to where found
- Flag personal Vs role based emails (support@.... Admin@.... etc)
- Flag email format (firnstname.lastname@...... first name_lastname@.... etc)
- Storing the details in an optimised database for fast searching.

I have neve setup anything like this before, so I am looking for proposals, to include your experience, about other things I need to consider.