If this is a problem for him now, childbirth is really going to be an experience. =)
The tampons and pads themselves are very simple. But, like toothpastes, deodorants, or soaps, there are a TON of options that get piled on by marketers. Wings/No Wings, Light/Heavy/Overnight/OMG, scented/unscented, Thong, etc. I must spend 5-10 minutes just trying to make sure I have the right ones that she likes. Is "Heavy" the same as "Overnight"? What did she tell me again?
It would be great if even ONE company tried to classify their items with a simple code number. If wifey just said "Hey, pick me up a pack of C-2s", I'd be a customer of that brand for life.
(Then we moved to a different country, everything changed, and now I have no idea)
It wasn't unusual for me (16 y/o at the time) to go in and buy:-
cans of coke
multiple packs of cigarettes (all different brands)
tampons/sanitary pads
condoms
2 gallons of milk, and 5 or 6 loaves of bread (when the restuarant ran out)
confectionary
toothpaste
etc
It certainly helped me get over any fear of buying these kinds of items.
I used to feel sheepish buying things for my girlfriend but I realized it's not bad for people to think you're a good partner. So instead of sullenly buying the hygiene products, I say go all out. Throw in some generic Midol and dark chocolate. No one will criticize you.