Every single Maker ID and Course ID out there plus some future ones that haven't been assigned to to-be-new players or courses yet (each text file contains one million IDs), includes IDs that also have been for deleted courses.
For Course IDs as they are sorted in chronological order when the course was submitted you can find the file that has the course ID you are looking for by searching for the file by date. For example, all courses in the 3,xxx,xxxth index are between 6/27/19 and 7/2/19:
Course IDs
0 L1J3KX48G --
1000000 S2KVLNV8G --
2000000 1XG3VTS8G --
3000004 4RFXV8WCG 6/27/19 (First known course in the game chronologically)
4000000 M6FLJ4S8G 7/2/19
5000000 QP0NL9Q8G 7/9/19
6000000 YJXVTGN8G 7/17/19
7000002 LJMDWR5BG 7/27/19
8000000 KTVCJRM8G 8/8/19
9000000 4BGFLXK8G 8/23/19
10000000 C5DNT3J8G 9/14/19
11000000 GNYPW8G8G 10/14/19
12000000 YFB5JDH8G 11/26/19
13000000 2YW6LKF8G 12/28/19
14000001 KJW5T959G 1/24/20
15000000 VNC3VJ98G 2/26/20
16000000 CGQJGNB8G 3/25/20
17000000 00BLJT88G 4/20/20
18000001 HK9KRK09G 4/27/20
19000000 BBTVT558G 5/10/20
20000000 T36BG968G 5/28/20
21000000 XLRCJG48G 6/19/20
22000001 JQ62RRM9G 7/17/20
23000000 CHQCTCS8G 8/14/20
24000000 V83TFHT8G 9/20/20
25000001 7JQLH7K9G 11/8/20
26000000 NLL3RTP8G 12/25/20
27000000 R365T0N8G 1/22/21
28000000 8WJLF4P8G 2/22/21
29000000 TR28GXL8G 3/28/21
30000000 2M0HP3K8G 5/4/21
31000000 F21R47L8G 6/18/21
32000000 NWXYCDJ8G 8/1/21
33000000 RDJ1GKG8G 9/12/21
34000000 D6G8PQD8G 11/12/21
35000000 RMGJ4VF8G 1/3/22
36000000 0HDRC1D8G 2/15/22
37000000 300TF6B8G 3/31/22
38000000 BTW1PC88G 5/20/22
39000000 P8X94H98G Future
40000000 X3VJCN78G Future
Maker IDs are also in chronological order of when the ID became registered to a user.
Maker IDs
1 XVVTJHX8G 6/27/19 (First known maker in the game chronologically)
1000000 V5VVLNV8G 6/29/19
2000000 31S3VTS8G 7/4/19
3000000 6JC5X0R8G 7/14/19
4000000 P9QLJ4S8G 8/2/19
5000000 SS9NL9Q8G 9/6/19
6000000 1N7WTGN8G 11/30/19
7000000 45TXWML8G 1/5/20
8000000 MX5DJRM8G 3/14/20
9000000 6FRFLXK8G 5/3/20
10000000 F8PNT3J8G 7/5/20
11000000 JR8QW8G8G 9/30/20
12000000 1KM5JDH8G 12/27/20
13000000 4277LKF8G 2/26/21
14000000 CW4GTQC8G 5/19/21
15000000 XRN3VJ98G 9/11/21
16000000 FK1KGNB8G 1/7/22
17000000 23MLJT88G 5/3/22
18000000 9XJTR078G Future
19000000 DF4WT558G Future
20000000 W6HBG968G Future
Maker IDs are also in chronological order of when the ID became registered to a user.
While Maker IDs start at index 1, for some reason course IDs start in the 3,000,000s.
Included is also a Java program that can be used to quickly convert back and forth between an in-game ID and actual index.