You just asked a question with a million-and-six possible answers.

Here are few suggestions.

1. Don't ask for a parts list first. First research ebike tech (motors, controllers, batteries) and what is available. Battery technology and maintenance are particularly important as batteries make or break a system. See 2. and 3.

2. Talk to Justin at ebikes.ca (Grin Tech) if you ever get the chance. He's an engineer who knows more about ebike technology than anyone else I know. His company can supply kits or components but with Justin that is almost secondary.

3. Join Endless Sphere. 'nuff said.

4. Then make your own informed choice based on what you've learned.

The first conversion is just a learning exercise so don't sweat that it might not be the ultimate solution. Unless of course you don't want to make it an ongoing hobby in which case you may as well just buy a good COTS conversion kit.