my fav ~ $15 white that is extremely popular is santa margherita pinot grigio. haven't met a white wine drinker that didn't like it.
i almost exclusively drink red. like ronjohn55 said, there's thousand's of choices for that price. see if you can get a california red, from 1997 or 98. you may get lucky and find some still around.
the coppolla family of reds are very good, and a lot of people are into the whole name thing. their blue label merlot or claret is very good.
A true lover of nature does not despair now that his mistress has turned a colder cheek.