Not really, the basic rules for poker are so simple that it requires next to no instruction. I would suggest you start out with No Limit Hold Em, which you probably intended anyway... most other forms work very similar. You should find instructional videos on youtube and the like. You can get a playmoney account on Pokerstars - their client runs with wine, and start playing against real opponents. It has little to do with real life gameplay, but you will get the basic rules.
A good place to learn more is
http://twoplustwo.com/ They have some excellent articles.
There are regular freeroll tournaments on full-tilt-poker. This is one of the few sites that offer freerolls for members without a cash account. I don't think it works with wine though.
The absolute best way, of course, is to play with friends. Body language is a very important part of the game when you play against inexperienced players, and it makes the game much more interesting... at least for me.
Have fun, and remember to gamble responsibly.
And if you want to watch some excellent poker, look for High Stakes Poker... some guy uploaded all seasons on youtube - look for 'Vailerth'.
Poker After Dark is also great, because there is not a single hand cut out. You see what's really happening, and not just the highlights cut together.
If you intended to start playing for money, I highly recommend you read up on bankroll management. This is a part that cannot be overestimated.
