Hello! First, thank you for your positive feedback on my previous post, I'm glad you liked the top^^! Okay I chose to answer some of your questions here because I think it might be helpful for other readers as well.
Where can you buy Japanese sewing books/magazines? My favourite seller is Pomadour 24 on ebay with her shop Simply Pretty Japanese Beads Books. Megumi has the latest publications as well as some rare books, not only for women clothes but also for kids and she has an excellent selction of crafts books! I have also ordered from Amazon.jp in English with satisfying results :) You can also try Yesasia, Fujisan and some Etsy shops.
Are the instructions in English? I have dozens of these books from various publishers and so far I haven't found any written in English. I know they have translated a few ones to French so maybe they will publish English versions in the future. About finding pattern pieces on the sheet don't worry, designs bear a code like C3 or simply a number and so do the corresponding pieces :)
Are there any seam allowances? No, you'll have to add your allowances!
If you have any other questions regarding Japanese sewing please ask, I'll answer here. See you!