Done that trip several times now...
You pay 1,75$ for a single fare just to get downtown (Loop) or $2 if you want to transit to another train or bus, or the $5 Day-Pass for the CTA
. The trains leave in terminal 1, CTA
The trip downtown (Thompson Center in the middle of the Loop...) takes about 45 minutes, from there you can connect to many other lines, especially going to the townships in the North and South.
A Cab costs you about $35 plus tip, a shuttle bus...don't know... So if you do not carry too much luggage, the El (our subway and elevated trains) is the best way I guess.
Drop me a PM
and I can help you more with what trains and where to go.
I can also help you to find affordable hotels, if necessary.