I will preface this by saying I am not very knowledgable of the earlier eras. This list is essentially post-2000, so I'm sure people will have suggestions to add, and I would love to make this list more representative of all eras. So forgive the recency bias, and please let me know who you think you should be on here.
Top 10 HS Distance/Mid-D Track Athletes
1. Jim Ryun - (3:55) Amazing time given the era, took almost 40 years to break, win over Peter Snell.
2. Gerry Lindgren - (8:40i/13:44) Also amazing times given the circumstances, took many decades to break.
3. Hobbs Kessler - (1:48/3:34/3:57i/8:39) Indoor mile record holder, outdoor 1500 record (faster than the ncca record at the time), solid 2 mile closing in 56.
4. Lukas Verzbicas - (3:59/8:29) Untouchable 2 mile record, no one within 4.5 seconds even including conversions, only ever triple at NBIN.
5. Alan Webb - (1:47/3:53) Mile record holder, 1 second behind Lagat, very good 800.
6. Colin Sahlman - (1:48/3:56/8:36*) Best range ever?
7. Drew Hunter - (1:48/3:57i/7:59i) Former record holder in the indoor mile and 3000, the comeback.
8. German Fernandez - (4:01*/8:34) Second all time 2 mile excluding 3200 conversions, 4:00/8:34 16/32 double.
9. Lex Young - (4:01/7:57i/13:43) Second all time 3000, second all time 5000.
10. Galen Rupp - (4:01/8:03/13:37) 5000m record.
HM: Rudy Chapa, Jeff Nelson, Simeon Birnbuam, Nico Young, Steve Prefontaine
*1600/3200 times converted to mile/2 mile. 1500 and 3000 left as is.
Probably more gaps to be filled in in XC, give suggestions
Top 10 HS Cross Country Athletes
1. Dathan Ritzenhein - 2x foot locker champion, numerous course records still standing, 14:10xc, 1st at USA u20, 3rd at world u20
2. Lukas Verzbicas - 3x national champion, only boy to win 2 in one year
3. Nico Young - nxn champion, former meet record, 13:39 3mile xc
4. Edward Cheserek - 2x foot locker champion, holmdel record.
5. German Fernandez - 14:24, 11th at world u20.
6. Colin Sahlman - running lane champion, 14:26 Woodward, 14:03xc.
7. Grant Fisher - 2x footlocker champion.
8. Ruben Reina - footlocker champion, course record (can be moved higher if someone can verify that the course is the exact same as it is now).
9. Casey Clinger - 2x nxn champion.
10. Leo Young - runner-up at running lane, 14:25 at Woodward, 14:05xc, 1st a USA u20, 16th at world u20.
HM: Chris Derrick, Lex Young, Abdirizak Mohamud, Aaron Sahlman, and many others
Apologies for leaving off any obvious names. Please share your thoughts!