Knitted sweaters shouldn't be washed in a machine, because the machine can snag the yarn and unravel part of it. And, you would have no idea this was happening to stop it until after the wash cycle and the damage is done.
Hand washing knit sweaters is easy. You just fill the kitchen sink about half way with warm water and pour in something like Woolite as a detergent. You then dip the sweater into the water and swish it around with your hands. The idea is to get the water and detergent passing through the knit cloth. This is what cleans the cloth (and it's basically what your washing machine is doing). Avoid picking up or pulling at the sweater, so you don't stretch out the part you're holding.
After a few minutes, drain the water out of the sink and use the faucet to rinse off the sweater (warm or cold water). When you've rinsed most of the bubbles off of the material, you can then refill the sink and swish the sweater around again for a final rinse.
After rinsing, squeeze the sweater material to wring out the excess water. Don't twist it though, as this can cause stretching of the knit material.
To dry the sweater, put a couple of towels down on a flat surface that's big enough for the sweater to lay out flat. Leave this to air dry, turning occasionally. It may take a few hours, depending on the temperature and humidity. And, you should turn it every half hour or so, again being carefull not to pull or stretch it out.
Or, take it to a dry cleaners, pay the five to ten bucks, and pick it up the next day.
In the US sweaters are traditionally knit on straight needles. Most sweater patterns you find will still be that way. The circular needle revolution was largely a result of the efforts of Elizabeth Zimmerman.
Honestly, your best bet is the sweaters from "The Knitter's Handy Book of Patterns" which is often on sale at knitpicks.com for 40% off. It contains patterns for all your basic knitted garments (hats, socks, mittens, sweaters, etc.) in all sizes and for all yarns. They're very basic designs that you can modify and embellish to make whatever you want.
Here's one example of a mens' sweater knit on straight needles and seamed:
Look for patterns with set-in sleeves and no fairisle and they will almost certainly be knit on straight needles. The only exception is the neck. The instructions almost always call for picking up stitches to knit around the neck.
Here are some others:
http://c2.lionbrand.com/cgi-bin/patternF... (note: you need to register to get the patterns, but it is free and spamless).
The simplest pattern I saw in my quick check, and it IS knit on straight needles, is this one: http://www.lionbrand.com/patterns/90041A...
I cannot teach you all the ins and outs of knitting in the round in one YA question. But an excellent place to start learning all you need to know about it is http://www.knittinghelp.com/videos/advanced-techniques
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Here's why you didn't get an answer last time: it's the section you posted this in. It's posted in "Fashion and Accessories" while all the actual knitters (as opposed to fashionistas) hang out in "Hobbies and Crafts." I found this question by chance with a search. I'm a knitter. I make beautiful things but it is the making, not the wearing, that interests me.