In Wisconsin, it's not too bad or expensive to buy a cycle and do the paperwork to get the title later. NOT having a title handy is good incentive for the seller to get rid of the frame CHEAP.
In my
BUILD YOUR OWN ELECTRIC MOTORCYCLE instructional DVD, I have an entire chapter dedicated to title, license, and insurance.
The main thing for all three of those is to make sure you know what you are doing, and what you want when you are all done BEFORE you start your project.
In some states/countries it is VERY difficult to get a replacement title. In that case, I would recommend that you absolutely make sure to have the title with your cycle. On the other hand, some people just want a cycle for "the back 40" and will only be using it on their own private property. In that case, there's really no worry for title and insurance.
I knew one guy who built an electric motorcycle from scratch. He made the frame and EVERYTHING. However, he thus didn't have a VIN, and it would have been a fair amount of work and expense to get it titled and registered. Even then, it wouldn't have a made and model for the insurance company. He ended up simply dismantling it and using the parts in other projects.