I will also send out the lease termination notices using either process server or certified mail.

Companies like Amazon have invested quite a bit of money into warehouse space in and around Des Moines for server farms. 

@Jess White I have one tenant who is a server.

I scrape my data directly from the county GIS server though, and it's basically the same data, although I have to figure out who's an absentee myself by comparing addresses (and the conventions like St vs Street aren't always consistent so it's harder than it sounds).You can probably just go to your local assessor's office and see if they can get you a spreadsheet.

If they have too many customers, and can't store the data on their private servers, (Not enough disc space) they will hire it out to a large facility that will hold a ton of data. 

Facebook is putting in a zillion $$ server on 400 acres and more as Atlanta being the corp head quarters of the SE.In an area with growing jobs, you will also see few rentals,,, make sense? 

Hire a process server who is as close to the property as possible and have them serve the the tenant according to Illinois Law.

I have also been working part-time as a server in a restaurant to supplement my income.

My brother has a constant monthly salary (web developer), whereas my monthly salary is more random (restaurant server).

Attractive servers are tipped better, attractive women are given breaks on their rent, etc.