You can easily make your own cleaner. All of the various eyeglass, LCD and electronics solutions you see out there are simply alcohol and water mixture. You basically want to mix 50% and 50% isopropyl alcohol. So you if you go to a place like Walmart, you can buy a bottle of 90% or 95% isopropyl alcohol for around $2.00. Then simply buy an empty spray bottle. Mix about 55% alcohol and 45% water in the spray bottle and there you go.
Use a microfiber cloth for best results. I've been cleaning my eyeglasses, sunglasses, RPTV's and laptop screens with this solution for years.