Missing, wanted applications

i have recently bought an ipod touch 8 gb at a pawn shop. everything was going fine until i decided i didnt want the songs that were already on there anymore. so i downloaded the itunes store so i could put different music on there and later on that day i went through a process tthat i thought would do the job for me. turns out the itunes browser reset all the original first bought settings for the ipod now i dont have the applicatinons that i wanted because 1. i didnt save them and 2. i didnt buy them in the first place! How do i get my applications back?