On a Mission from God
Join Date: Oct 2009
Location: Thibodaux, LA
Bikes: Surly LHT, Rat-rod Klunker
If you want to stay under $800, you need to go with the basic, no-nonsense parts to get your bike rolling. I know lots of guys will fuss at me for not recommending high quality parts, but the important thing is to get the bike finished, You can upgrade parts as you need to, but the main thing is to get a setup that's comfortable.
For commuting, you might want plain straight bars, or use bar ends. A lot of folks use Trekking bars (like me) and like them a lot. Cruiser/arc bars work fine, too. You also need a good saddle (good is relative, just get one that fits and is comfortable). Everything else is negotiable.
You're going to want a way to carry stuff, so look into a good bag, or a trunk bag, cheap panniers, etc.
You could go with a SS setup, it depends on your route, and if you have hills, etc. I could get away with it here, I live in Louisiana... but I'd rather have gears in case I need them. I've used some IGH setups, they're not the cheapest, but they work well. You might be fine with just a 3-speed, you can get some really nice ones with all kinds of brake options.
Since it's going to be ridden hard, and in winter, I wouldn't worry about putting tons of money into components. Get good, solid wheels. Nothing flyweight, you want reliable and maintenance-free.
You can look into other things like lights and fenders, but again, that's your preference. All you really need is the bike, and a desire to ride it.