I have to start this entry off with saying that I'm not anything even remotely like a gambler. Oh, I've been known to enjoy a few hours at an online casino's (virtual) poker table playing Texas Hold-em, and I watch the world poker tour and the world series of poker occasionaly. I enjoy both watching and playing and yeah, someday I'd love to be able to afford to buy a seat at the world series of poker.. But on top of all that I am not a hamster. I know full well that it's going to be a LONG time coming before I can afford the $15,000 buy-in that it takes to play at those tables.
In the meantime I limit myself to the stuff on tv and some occasional freeroll action online... I simply stop short of allowing any real money to get involved. In doing this, I've seen quite a few online casino sites. It's amazing that, regardless of how many reputable ones there are, there's a lot of crap out there too. Pro360 online is a resource designed to help weed through what's out there and find the better sites that have the games you're interested in.
This site has listings of sites divide by category. each entry has review both by the editors and by players. Pro360 online has been doing these reviews since 1997 so they've got some experience that the newer sites don't have. If you're interested in online gambling, then be sure to look around before playing anywhere, especially if you're using real money. Other than that, set limits on both time and money and stick to them.