I can't seem to find any screenshots of (preferably good) electronic voting systems. I mean the kind that's used in elections. Any ideas where I can find one?
If you want to read research on and analysis of the design of user interfaces for voting systems, I recommend reading the work of Mike Byrne (at Rice), Whitney Quesenbery, Dana Chisnell, Ben Bederson (U Maryland), Juan Gilbert.
I can also highly recommend the Usability Professionals' Association Voting and Usability Project. They've done some great work on usability of voting systems. Between the above resources, you should be able to find a great deal of information on UIs for voting machines.
If you really just want some screenshots, googling the name of the voting machine should find you screenshots. Some popular electronic voting machines include Diebold AV-TS, Diebold AV-TSX, Sequoia AVC Advantage, Sequoia AVC Edge, Hart-Intercivic eSlate, ES&S iVotronic. Verified Voting has a guide to the most widely used electronic voting machines that may be helpful.
Please note that in the context of elections, all electronic voting solutions have one important drawback: they obscure the process that by the very nature of it should be as transparent as possible. It becomes impossible to follow your individual vote and see that it is handled correctly, while still keeping that vote anonymous. At least, not without very complicated technical solutions. That does not really add transparency, as the point of the transparency is that the average voter can understand and verify the process.
No user interface, no matter how sophisticated, will solve this basic problem.