In terms of convenience, their convenience stores (also known as konbini) are so convenient that it's not strange to find 3 konbinis that are just a few meters away from each other. For crafts, I love Tokyu Hands [12-18 Udagawacho, Shibuya] (DIY, craft & office supplies, cooking tools etc. where you'll probably spend the whole day in it because most stores have 7-9 floors for you to explore, no joke!). And as a bookworm, Kinokuniya [Japan, 〒151-0051 東京都渋谷区 千駄ヶ谷5-24-2 タカシマヤタイムズスクェア] is my best bet for English books! I like Loft [21-1 Udagawacho, Shibuya], MUJI [Japan, 〒101-0025] and their ¥100 shop (similar to a dollar shop) too!
In terms of craft shops, head to Tokyu Hands [12-18 Udagawacho, Shibuya] for almost anything, Yuzawaya [Japan] for fabric or accessories, Nippori [Japan, 〒116-0014 東京都荒川区 東日暮里5丁目33−10] Sen-i-gai which is a street full with fabric stores (more than 80 stores) and ¥100 shops Can Do [2 Chome-1-5 Sanno, Ota], Daiso [2-2-1 Kinshi, Sumida] and Seria [1-22-6 Jinnan, Shibuya].
Tokyu Hands [12-18 Udagawacho, Shibuya] actually has a corner in their store for selling handmade items or you can also set up an online shop in their website too (something like Etsy). There is also a weekly event at Yoyogi Park [2-1 Yoyogikamizonochō, Shibuya] where everyone can sell their handmade items (crafts, food or anything).
As I have allergy to seafood, I can't eat sushi at all (totally wasted!) but glad that I found my favorite food here which is their curry rice (my fave is CoCo ICHIBANYA [3 Chome-8-5 Nishihara, Shibuya] as I can choose the level of spiciness). And as I love trying new food, I basically try new places whenever I can.
When I crave for something sweet, I love going to Harajuku [Harajuku] (Takeshita Doori) for their crepes and Nishiyama at Asakusa [Asakusa, Taito] for Japanese traditional sweets. But sometimes the wide range of sweets sold in their convenience stores are more than enough.
I don't drink so I rarely go to their Izakaya (Japanese pub).
I'm not sure where is best to craft in public as I usually do my crafts at home.
You can meet your new crafty friends at craft classes or handmade market!
Visit Takeshita Doori [Jingumae, Shibuya] at Harajuku or Yoyogi Park [2-1 Yoyogikamizonochō, Shibuya] on Sunday to catch a glimpse of the quirky side of Tokyo, Shibuya Crossing to see a sea of people crossing a street in a count of seconds, or Shimokitazawa for a vintage side of Tokyo.
Everybody tends to buy "Tokyo Banana" (banana-shaped sponge cake) as a souvenir though personally, I'm not into it. As a souvenir, I prefer buying their "o-mamori", an amulet that you can get at temples. For edible souvenirs, I prefer their Kit Kat chocolates because they have the most bizarre flavors in the world (think hot chili and wasabi)!
As a vibrant city (filled with the most random stuff I've ever seen), there were times where I just got inspirations by just walking around the city. If not, I usually go the ¥100 shop because they have almost everything and sometimes they spark something :
Japan has a lot of festivals and I enjoy their them very much. For example, the "setsubun" festival that happens in February where you throw beans around the house to repel bad luck and eat a big roll of sushi in a complete silence, "hanami" or sakura-viewing festival and more.