I'm a die-hard PPC fan, but honestly I think an '09 or '10 Macbook or 13" Macbook Pro would serve you a lot better. Shop around and you can probably get the Macbook for less than $200-an early '09 or later Macbook will run the most current OS(10.10, and 10.11 when it's released this fall). Any 13" Macbook Pro will also do this, although it will cost you a bit more than a Macbook. If you want a desktop, look for a Mini from around that time.
As eyougren said, you have to deal with a lot of compromises with PPC Macs. I love them and love making them still relevant, but it gets more and more difficult with each passing year. I'd be afraid that using an iBook or Powerbook would really give you a somewhat poor Mac experience. There are also compromises in the fact that original batteries are now on their last legs for the most part and replacements are either not very good or as expensive as the computer itself. Even with a "good" battery, the battery life tends to not be great for surfing because the modern web is so bloated.
If you are going to get a PPC Laptop, look for either an iBook G4 or an aluminum Powerbook. Both of these will at least give you an Airport Extreme card(or at least the ability to install one) and can still connect to virtually all WiFi networks when running 10.4 or 10.5. The original Airport card can't even see the WiFi networks at the university where I'm employed. If you want to get a desktop, I'd highly recommend either a G5 tower or an iMac G5.