Every drug store/pharmacy in the U.S. carries a wide variety of both condoms and lubes (CVS and Walgreen seem to be on every other corner).  Many supermarkets and mass-merchants like Target also carry them.  All are merchandised in the regular aisle, not behind the pharmacy counters.  Look for the aisle marked "Family Planning" (I always get a kick out of that).

Stick with well-known brands like Trojan and Lifestyles and you'll be fine.

.... if you are not in a rush to hobby yet stock up on lube or condoms from condomjungle.com or condomdepot.com