Flights: I just book em far in advance and compare what it costs to go direct through the airline or a discount site.
Backpack: The Osprey Far Point 70 has been my goto for about 7 years now. It's 2 backpacks in one. It's a 15 L and a 55 L. The 15 can clip to the 55 in multiple ways. Preferred setup for skating through the streets is so it sits in front of me. If I didn't have a digital slr with flashes and multiple lenses, I wouldn't need this bag and would opt for something smaller. The day bag has chest and waist clips which is great. I'm also usually traveling with a tent, sleeping bag, sleeping mat, inflatable pillow (compresses to less than the size of a fist), so this bag has room for all of that. I try to choose flights that allow me to check the 55L bag with my board attached to it.
Sleeping: Major cities check hostels first, then airbnbs, then booking.com. If it's just me and 1 other person and we are renting a car, try to get a van so we can car camp. If it's multiple people and we are renting a car and traveling, scope out camp sites in between major cities (free or cheap).
Maps: Google for sure if it isn't China. Just pin the spots you want to check out and save the map to your phone beforehand.
@sexualhelon, your map is super rad. Makes me want to visit Taipei.