This was changed at least a year ago. It has also been discussed dozens of times in these messageboards, to include THIS ONE only two weeks ago. There is no limitation on access from an NPC, but I agree that the Fame cap is probably the best option, which given the low scribing and access costs isn't really much of a limitation.
Bottom line, you don't have to buy scrolls in order to copy them into your spellbook anymore. Your options to learn new spells for your spellbook are:
1. Adventure with another wizard or magus PC, and agree to exchange access to your spellbooks. Only pay the scribing cost once you've made your rolls.* Shinobikazuma has the scribing costs listed above. You are not allowed to charge other PCs for this access.
2. Loot the spellbook from an enemy wizard or magus that you've defeated. Ask the GM what spells are in it. Make your rolls* and scribe the spells you want, paying the appropriate scribing cost for ink, etc.
3. Find scrolls on the bodies of your enemies or just lying around, and assuming that you don't need to cast them off the scrolls during the scenario make your rolls*, pay the base fee, and scribe them into your spellbook.
4. Go to an NPC spellcaster or library between scenarios, pay your access fee (half the scribing cost), make your rolls,* and pay the normal scribing costs.If you're buying a scroll just to copy a new spell into your spellbook you either haven't read the FAQ in at least a year or you have thousands of gold pieces you want to throw away.
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Hey Dan (or anybody else as well), do you know where the original source for #4 is? i did not see it in the FAQ or the current PFS guide....