Stream it directly from the FIA [about $12]
This is the official feed directly from the FIA, the sanctioning body that oversees the Le Mans 24 Hours. The price is 9.99 euros, which is $11.25 today. You can go to the FIA WEC site to sign up as a member. There are also options to get streaming for the whole season with or without Le Mans (who doesn't want Le Mans?). Lest you be tied to a desk for any more hours this week, we have some hints on how to get what you're seeing on your computer to show on your TV screen at the end of this post.
Stream it from Fox Sports Go [requires cable login info]
If you have a cable subscription (or, uh, know someone who does...), you can stream the whole race from Fox Sports Go, either in your browser, through an app on a phone or tablet, or on an Amazon Fire TV. You can also throw the feed to an Apple TV or Chromecast from a computer or mobile device; see below. Logging in requires your cable carrier username and password.
Watch most of it on Fox Sports 1 and 2 [requires cable]
Fox Sports has the rights to broadcast the race in the US. You can't see the whole thing start to finish that way, but you can catch most of it. Think of the gaps as a way to enforce breaks for sanitation and hygiene matters. Coverage flips back and forth from Fox Sports 1 and Fox Sports 2, so you'll want this schedule by your remote:
FS1: 8:30 AM to 2:00 PM Saturday
FS2: 2:00 PM to 4:30 PM Saturday
FS2: 6:00 PM to 6:30 PM Saturday
FS2: 7:00 PM to 7:30 PM Saturday
FS2: 10:30 PM Saturday to 2:30 AM Sunday
FS1: 2:30 AM to 9:30 AM Sunday
Listen to Radio Le Mans [free]
No visuals with this option, obviously, but you get the expert announcing and coverage from people like John Hindhaugh, who has been covering the race for over 25 years. Consider playing the audio stream over one of the other video feeds on mute. It's also a good option if you're busy doing something and can't watch a TV, like open-heart surgery or something. Go to the Radio Le Mans site or get the stream from TuneIn.
Follow live timing and scoring [free]
The FIA provides position and lap timing info in text form for free (or gratuit as they say in France). It's no substitute for watching or listening to the race, but it's a nice thing to have open while you follow along. So factor in one more device for that. You can find that on the FIA WEC site.
How do I get the stream onto my TV?
There are lots of ways, but they depend on what equipment you're working with. If you have a computer with a wired video output that can go to your TV's HDMI port, setup is relatively easy. You can also send the signal over WiFi from a computer or device to a box like the Apple TV or a Chromecast. The Apple TV will let you send video from an app or computer screen using AirPlay, and with Chromecast you can cast the contents of a Chrome tab from your device of choice.