The site sajha keto mentioned (https://cgifederal.secure.force.com/) does not look credible to me. This is the official site (.gov): http://travel.state.gov/content/visas/en/general/wait-times.html/

Re: appointment: Few years ago, my family member was able to set up appointment emailing the Consular at KTM, and paid all fees inside the embassy (not bank) on the same day of interview.