Check the fvcking date on the package before you buy/use condoms. (Yeah, condoms have expiry dates and all.) Store them in dry and cool areas... Heat and humidity can damage your condoms even in packaging. I recommend a tin can of some sort, so just like Jester said, use an Altoids box.
Jester forgot to mention that besides latex and lambskin condomse there is a different kind I heard about... Something along PVC materials being used to create these ultra-sensitive condoms for all those folks allergic or just plain annoyed by latex. Check askmen.com's Sex section, it might still be there.
Also, investigate different types of condoms (ribbed, extra-safe, etc.) because they might bring a whole new punch to your performance/feeling.