I don't think there is anything that will convert an exe to .apk. It's not that simple... Your taking code from a totally different os (windows) and porting it to different device and os. If you have the graphics and resources you could rewrite the code for android. I'm assuming you have coding experience if you created the .exe's. Which language did you write the games in? Android uses java, which is very similar to C, the hardest part would be learning the android api's and how android works. I'd suggest getting a book on java, and a few books on android game development.
Not sure if you can make games with it, but there is a drag and drop tool for creating android apps: android app inventor: http://www.appinventor.mit.edu/
Not sure if you can make games with it, but there is a drag and drop tool for creating android apps: android app inventor: http://www.appinventor.mit.edu/