The Louvre does not offer anymore tickets at the stands, you need to buy your tickets online in advance.
I recommend you buy tickets online from the official website, 2 to 3 months prior the Louvre guided tour.
I can purchase the tickets for you :
Be careful : all tickets are personal with your name and date on it, so you can't buy it from an app or else !
Please tell me in advance your date, your name and number of people, so I can buy the tickets before they are sold out !
This is where to go to check if your tour date is still available :
Your Louvre tickets should look like this.
Please verify with your provider that you have your name & date & hour & a bar code on a pdf ticket from the official Louvre Billeterie
00:00 – 00:00