Twitter. It's pretty easy to understand once you do understand it. Most poeple don't post "waking up, going to the bathroom..." anymore. It's more advanced. In fact Dell computers ran some specials and made millions from twitter.
The easiest way to find someone to follow is go to their website or blog. You'll usually see some place that says "follow me" and some icons. The 'T' is twitter, 'F' is facebook, etc. it will direct you to twitter, you sign in (if you need to) and click Follow. You can find some on yoru local tv new channels (I follow the weather one for my area) or newspapers too.
You can also search for specific people and place on twitter. Celebs usually use their name and it will say something like "verified" or "cerified" which means it's the actual celeb.
I liked to follow engadget. A few articles are reposted here on DF. GoogleMobile is another good one.
You can then send Tweets too. I don't send many. Just whatever you want. 140 characters or less.
Retweet is a forwarded tweet. If you like a tweet, think it's informative, etc., you can choose to Retweet.
You do not have to follow everyone who is following you. Or even very many people. I have some "ads" that follow me but I don't want their ads so I just ignore them and don't follow them.
Icons:
Tweets--messages from people on Twitter
Lists--any lists of people you or someone else creates that you follow
Mentions--if anyone mentions you (such as in a Follow Friday list)
Retweets--If you want to see these exclusively
Messages--I guess if someone sends you a message
My Profile--you, your pic, etc. I'd suggest keeping it to a minimum.
Trends--Just whatever everyone is talking about. people add a hash mark (#) before a word and it may trend, or what others are talking a lot about. Not always the hash marked words either. For example, #honeycomb is trending. you can click on it and see what others are saying about it.
Search--you can search twitter (never used it so that's what I think it's for).
You can also see what others have retweeted or what's trending and click on their profile and tweets. If you like them you can follow them.
Hope this helps.