Also don't forget to check stores such as Electronics Boutique and Game Stop, that is, if you're in a country that has stores such as these, that sell old/used games. These stores are better for those who would like to avoid the whole "online purchasing" deal.
In any case, these are the stores where I found Abe's Oddysee and Exoddus.
![Cool Fuzzle](images/smilies/fuzzlecool.gif)