Hi! I'm Tiffany, and I'm one of the writers for Tokyo Cheapo and Japan Cheapo. I've been living in Tokyo's Ikebukuro area for nearly three years. I agree with Adriana that Ikebukuro is a lovely place to visit and live in. Tourists tend to skip this area, but I think that it's worth checking out. It's got great shopping and entertainment options, and if you like anime and manga, I would definitely recommend visiting Ikebukuro. I once took a visiting group of students to Ikebukuro on their free day, and all of them had different interests (fashion, electronics, anime and manga, etc.), and all of them managed to see and buy what they wanted, so everyone went home happy.
I'm from the Philippines, but I moved to Tokyo for grad school. Last year, I got my MA in media studies, and now I'm working as a copywriter for a marketing communications firm. I enjoy reading, writing, traveling, taking pictures, making crafts, and cooking (really new to it, so I still have a lot to learn, but I like trying to make new dishes, even though they don't always end up looking good). Also, I collect postcards, and I just got a shuincho (a book for temple seals/stamps), so I might start collecting those, too. Lastly, even though my everyday fashion sense is very ordinary, I like dressing up on occasion, which includes cosplaying and putting on kimono (someday, I'll learn how to wear one!).
As for my top cheapo tip, visit restaurants at weekdays during lunch time to enjoy cheaper meals. There's usually a vast difference between the prices of lunch and dinner menus. Although some restaurants do roll out the better stuff at dinner time, in most cases, you can usually still get a signature dish of theirs (or at least one of their better-known dishes) for much cheaper at lunch time. You can get better value for money, too, since lunch sets usually come with something on the side, like a drink and/or dessert.
I have another newbie tip, too! This is more for those who'll be living in Tokyo for a while, but... if you want to meet new people, Meetup.com is your friend. It may not be that popular with the Japanese, but you can make friends not only with fellow foreigners, but also with Japanese, usually those that are open to befriending foreigners and able to speak at least some English. It's especially great if you're a hobby-oriented person!