Yes, please do. I've been making a killing on flipping Vile Wards the past few days.
As for new/returning players, I have no idea what compels people to post things on the AH without knowing the current market value of items, but I'm sure glad they do. Two months ago I returned to the game, and was broke and mostly clueless. I bought 100 million, and turned that into a little over 2 billion worth of items. I've had one lucky item drop that sold for 800m, and after selling all my old Barb gear I've assembled a 200k dps CM Wizard. I've also "won" about 100 million worth of shit from twitch.tv streamers giving away gold/stuff. Watching streamers is as boring as it sounds, but I keep them on a second box, and have 3 or 4 going at once and glance over when they announce a giveaway. If they want to give me gold and items for me to put their stream in my background, great. Streamers also are a great way to get a pulse of what's going to be popular on the AH. I flipped a ton of shit during the farming contest last weekend from people who apparently saw the Wizards out farming the Barbs and Monks and decided to start their own. If you like drama, there's that too with the Euro's. Seemingly none of them can get along with each other.
I also sold a few items to have a few dollars on the RMAH. I've snagged two nice items that was listed for $2.99, with a $250 buyout. Only insane people would spend $250 on an item, so you can occasionally get them for the listing price especially since the max gold AH buyout is 2 billion, and 2 billion in gold is much cheaper than $250. So I always keep $10 or so in my account so I can snipe an expensive item for cheap on the RMAH.
So if you're new to the game, or a returning player with a limited bankroll and a patient personality you can build yourself a decent set of gear with a little work. If you're an OCD type over having the best gear possible as soon as possible, and you don't want to spend a lot of real life money, then D3 might not be for you until the expansion/PS3/4 console.