@duncan, I would highly highly recommend that you read through ALL of the posts of the website before you start posting. Chances are that someone has either had the same question as you, or has already posted something about your question.
As for batteries and supplies check out the BOM:
https://bitbuilt.net/forums/index.php?threads/portablizing-bom.367/
Please read the Definitive Wii Trimming guide before asking about where to put things. The pro's have spent hundreds of hours putting it together. One reason was to not have to answer this question for every single person that asks.
If you aren't going to do your own research and read though this website on your own, I can guarantee that you will have a really difficult time.
I would highly recommend that you follow this process in portabilzing:
#1. Make a goal of what you want (perhaps a wii portable or n64p)
- Be very specific on what you want. Do you want it to be landscape portable? What size of screen do you want? How do you want the case to look?
#2. Write down a list of all the things you are going to need. Obviously you want a screen, the console, batteries, controller, etc. Write down how much they cost and the total cost of the project.
#3. DO RESEARCH. don't just hop online and asking blind questions expecting everyone to jump to help you. this is a Do-It-Yourself modding community. We DO want to help, but we don't want to waste our time on people who aren't considerate enough to learn for themselves.
If you keep posting, demanding questions without doing any research you most likely will get banned.
#4. Buy all your things
#5. Make the portable. If you have questions, you can ask about specific issues or techniques.