From an outsider's perspective, in the US it seems that condoms (and from what I understand, all kinds of birth control) are particularly hard to get hold of when you're under age.
In Britain not only is the age of consent lower than most states - but condoms, the pill, the morning after pill, diaphragms and the like are all fairly easy to get hold of - although I guess having socialised medicine doesn't hurt in that respect.
Is it only the condom manufacturers that are offering free condoms (and samples at that; so not exactly out of the goodness of their hearts) rather than a national scheme to promote safe sex or are there other (not commercially-minded) initiatives going on?
I was just reading about Nancy Pelosi putting something in a new stimulus bill about making free contraception readily available, and a bunch of people getting all fired up about it. There's no national scheme that I know of right now. The closest thing is that most universities have a place on campus that gives them away, along with other services like counseling. Mine even has free condom delivery to anywhere on or near campus, 24/7.
There is no age requirement to buy condoms (as far as i know) but i know that many places have them behind the counter. I noticed this once and asked why and the reason is because apparently they are a high theft item. But even then i'd say do some research. There are a LOT of community groups out there that are ready and willing to basically throw condoms at you.