Here is a little information put together to help identify what version PSP you may be, or may have, purchased.
All this info has been gathered from numerous PSP users from around the net. This not a definite guide, and I am not responsible if any of the information is correct or not. Use this at your own risk, and report any errors in this thread or PM me.
** Confirmed **
None = 1.50 US Launch Value Pak
A = 1.50
B = 1.51+
C = 1.52
D = 1.52
E = 1.52
F = 2.0
G = 2.01
H = 2.50
I = 2.60
** Not confirmed ** NONE
Here is where you locate the letter from the above chart:
What are my chances of finding a PSP with X firmware ?
The best chances to get a 1.50 - 2.00 is to find a small city/town with a Wal-Mart or Hobby Shop. Retail stores in larger cities tend to sell out of everything really fast. Therefore their stock usually consists of the latest releases. Smaller towns/cities usually don't sell out very fast. A local Wal-Mart 10 miles west of me still has 10+ 1.52 version PSPs. That is on the shelf. That doesnt include what may be stocked in the back still.
So your best chances are with smaller stores in small towns.