Where can I find real-time flight tracking with the least amount of delay? I am an aviation fan, relatively new to the industry.  While I thoroughly enjoy plane spotting at my local KORD airport, at times I tune to LiveATC and Flightaware to get my fix.

Unfortunately, my observations are that flightaware is a bit delayed 3-5 minutes, and not all air traffic is shown.

I tried Flightradar24, it is more current, but wildly inaccurate at times and a bit "synthetic" as they try to fill in the data gaps.

Aside from getting into an actual ATC tower, which I am sure is nearly impossible for a civilian, what are my best options as far as getting my fix in?  Apps, services, etc (paid and free), doesn't matter.
You can buy a DVB-TV USB stick for around €20, which will allow you to receive ADS-B data:



Up from that, you can get a high-end ADS-B receiver that costs about €750:



Finally, FlightRadar24 offers free hardware in selected locations:



Bear in mind that these devices will only allow you to receive signals within a relatively small area.

One thing worth noting is by contributing the data received by these devices, you get a free FlightRadar24 Premium subscription.

Lots more information is available at FlightRadar24 > Increase Coverage.