When I am playing the Sicilian Defense, I always start with 1.e4 c5 2. nf3 d6
The problem is that I commit the d- pawn. One setup I've struggled with is when my opponent and I make a few more moves, and then he moves c3 followed by d4. Does anyone have any ideas on this? Should I not commit my d-pawn so early?
2..d6 is definitely ok. It's been played by pretty much every GM ever, and still is. The basic way to deal with c3-d4 plan by White is to attack the e-pawn. For instance,
1. e4 c5 2. Nf3 d6 3. c3!? Nf6!
And now he has to do something about the e4 pawn.
4. Be2!? is possible, since 4..Nxe4 loses to Qa4+. But then I like 4..Nbd7! Stopping the check on a4 and threatening to once again take the pawn. Then:
5. d3 And Black is safe for a move or two, in which he can use to play ..b6 and ..Bb7, attacking the e4-pawn again.