Upload & Sell: Off
A) Sell images as stock. (they're sitting on my hard-drive, so why not?)
I know one photographer who makes a decent amount of money shooting microstock. But it's all 'lifestyle' type photography. People hanging out, smiling, playing in the park, that kind of thing.
B) Setup a website and sell larger prints of the high quality images I've taken. (figure this wouldn't tend to draw too many customers right away)
A website is never a bad thing to have. Though it does cost money to set up and maintain, at least if you want a nicer one and not one of them cheapo free photo snapshots gallery type of things. And the nicer your website, the more it will probably cost, unless you are experienced in web programming enough to set up a really slick site on your own. (My first two websites I built on my own, but I got so tired of trying to update and maintain them that I eventually decided to pay the money to let someone else worry about all that.)
C) Sell at art/craft type shows occasionally. (are these things really worth it? Sounds like a bit of work)
It is a bit of work to prepare. It's not like selling one-off prints online...you actually need to have physical prints ready to show and sell. I do this occassionaly...but more because I find it fun and enjoyable to get an opportunity to engage and talk to people about my work. Be aware that there are also expenses associated with this as well. At a minimum there is a cost for making the prints to have at the show and having a way to display them. The cheapest way is to display unframed and unmatted prints in a clear poly bag. When I do this I like to add in a backing behind the print (like foam core or thick cardstock) so they don't get all bent when being handled by people. You can also display matted prints in poly bags...a lot nicer but of course the matting materials will cost you extra. And of course, there are framed prints, which are never cheap to do in volume. The nicer your presentation, the more likely you are to sell something...but the nicer your presentation, the more money you are likely spending to make it nice. So unless you are doing huge amounts of volume in travelling fairs, don't expect to make a lot.