Yes - but mostly potions and scrolls, and minor items - anything else is more uniquely roll played, and I do do power items, as well, for crafting.
If there is magic in the world, inevitably, it will be traded. Unless your world is magic-dead, there WILL be magic sold, it is just a question of how many shops there are that sell it.
Heck, if the PCs want, at some point THEY could open a magic shop. If it is a world that supposedly has no such shops, they'd found the industry and they'd get SUPER RICH in doing so because of the lack of competition. That's the bonus you get for being the founder of a new market.
EDIT:
Ok, I just had to go back and say this, after reading the poll again. The concept of things NOT being traded for "just gold" I think is ridiculous - learn some economic theory and what money really is for and represents. If something can be sold, it can be sold for gold. Period. See, that's why an economy based on money is far superior to one based on barter. That's why you can have smooth transactions - instead of person A who has item A who will only trade for item C, and buyer B who has item B, not C, but can trade C for item C with B and then can trade with A with item C, etc. etc. etc. - see, with this thing called "money" you DO NOT NEED TO DO THAT. You just buy direct from A, for gold, and then A can buy from C, or not, at A's liesure. Any objection you can give about A not wanting to part with item A for "just gold" is really just dickering over the price. Heck, if it is truly the case that A could never buy item C from person C, but A really wanted it, if they sold item A for enough cash, they could just HIRE someone to go TAKE it from C. The free market always finds a way. And with money much more easily than barter.