Though Chicago is generally regarded as a city which is expensive, you will get plenty of things which you can do free of cost. There are several museums in the city which are not very famous. You can visit those museums free through out the year.

Some planetariums like: Adler planetarium offers free visit in some days. If you posses Chicago public library card, you will be able to visit Kraft Kids museum passport which will show you several attractions.

To know more about the various free things which can be done by the visitors, please log on to the following websites:

http://www.thelocaltourist.com/cities/chicago/free-things-do-chicago

http://www.yelp.com/topic/chicago-free-stuff-to-eat-and-do-in-chicago

Never book ticket through some stranger.

Check and verify the experience details and existence of travel agency, if booked for first time.

While booking through travel agent, always insist for booking voucher, Original copy of Air ticket, terms and condition guide.

If booked on line, do not forget to take print of the ticket.

Always try to keep the PNR number of your ticket handy, In case of some unfortunate incident or loss of ticket print out, you always have the opportunity of getting new ticket issued through PNR number.

http://www.tickets.cheaptickets.com