So, now you have a profiling amp - but nothing to profile? 
I can encourage every KPA owner to profile some tube amps for themselves - it' fun and you learn a lot.
What will you need:
a) KPA
b) Some cables
c) A Microphone (e.g. SM57 - is easy to use and needs not external preamp)
d) A great amp
Yes, where to get these amp(s):
a) If you own one or more great tube amps - that's best - you have plenty of time to learn to find the best mic position, amp settings, ... and can profile the amp with all available options (that's what I am after - I like to CAPTURE the amp in my KPA - not only some sounds of the amp)
b) Ask some friends and make a profiling session together - they may have the amp(s) - you have the KPA - and most guitar players like to learn about the KPA as well
c) Buy an amp - profile - send back
!!! That's not a fine way to get profiles - and if the shop finds it out later - they can ask for compensation because you actual USE the amp
But you can buy an amp used at ebay - profile - and sell the amp - most likely will you not make a lot of lost.
d) Rent the amp - some shops rent amps - so you can pay a few bucks and profile the amp you like
e) Go to a recording studio - profile all the amp they have (and you like) with high quality gear.
And more ideas?