I know there was a suggestion in these Forums some time back for a quest tracker with progress dialogue which received mixed support. Might be a good time to revive it.

Yes, to be able to select the blank line from the Tenshodo NPC you do have to have a certain fame level which I agree is ludicrous since most people groan when faced with collecting Yag Necklaces or Zinc Ores to turn in. Yag necklaces are a much higher drop rate than Zinc Ores unless you buy them. Honestly, the best thing for you to do is to earn that 30k and buy the invite, you can sell it right back. I know farming is boring, but if you farm the heck out of Saruta for Beehive chips and silk you can make enough to buy your invite. The other option is to ask friends if they have one they can lend you. In any event, you are going to have to earn that Tenshodo fame if you are looking at going after NIN because you can't get any of the :Ichi scroll quests without it and you will be shocked at how much Utsu: Ichi is.

Good luck in your endeavors.