Texas Hold Em is part of some of the research I'm doing for my degree and I do like to play. I'd be happy to answer any questions I can about the game.
In terms of playing online below is a link to a simple Java implementation of No-Limit Hold Em. It's not great and the bots are terrible (you say you wanted single player I think :/) but goes through the motions of the game so you'll know *how* to play.
http://www.games.com/game/poker-wsop-te ... -no-limit/
You say you want to learn poker, I'm not sure if you mean you know how to play and want to get better or if you don't know how to play at all so below is a quick summary.
Assume 3 players.
Player 1 has a Dealer Button.
Player 2 is left of Player 1 and therefore is given Small Blind.
Player 3 is left of Player 2 and therefore is given Big Blind.
The dealer button acts to show where play begins each round and shows which players should post blinds.
Blinds are fixed amounts of money added to the pot (see: ante) to ensure that money is always moving and that each player needs to pay to play.
A Hand (one round of play) is divided into 4 rounds:
1. Pre-Flop
2. Post-Flop
3. The Turn
4. The River
Pre-Flop
During this stage each player is dealt two-cards (Hole Cards) which only they know. By way of the dealer button the appropriate players place blinds. Following clockwise (normally) each player after the Big Blind player decides whether to play in the hand and chooses an appropriate action (Call / Fold / Raise).
Once all players have either called the current bet or folded the round ends.
Post-Flop
During this stage 3 cards are dealt to the table. These are called Community Cards and every player can use them along with their own 2 cards to make a 5 card hand.
Play begins from the first player still in the hand to the left of the dealer button. A betting round occurs (same as Pre-Flop) in which each player may have two situations:
a) No bet during this round has been made therefore they can Bet / Check / Raise / Fold
b) A bet has been made this round therefore they can Call / Raise / Fold
Once all players have folded or called the current bet the round ends.
The Turn
During this stage another card is dealt and added to the Community Cards. Now each player still left in the hand has 6 cards out of which they make the best 5 card hand. Another betting round occurs as before and when all players have folded/called the round ends.
The River
Same as The Turn. Another card dealt, now all players have 7 cards to use to make the best 5 card hand. Another betting round.
At the end of this round if there are still 2+ players left in the Hand we go to a Showdown stage.
Showdown
This stage simply means that all remaining players show their 2 Hole Cards and the player with the best 5 card hand (made from their 2 Hole Cards and 5 Community Cards) wins the Pot.
If at any point during the Hand the number of players in the Hand drops below 2 then the remaining player wins the pot automatically.
I hope that all made sense, any questions feel free to ask ^_^