Starcraft 2 is about the only game i really play anymore. Single player is just a part of it while i would say 90% of the people who buy it are interested in the multiplayer aspect of it.
Single player is a good place to start off if you know nothing about the game. Although i believe you only really get to learn Terran with it. Once you finish the campaign, i would recommend playing a few games vs AI to get a generally grasp of the game with other races or to further explore terran if youd like.
Once you feel pretty comfortable playing hard/very hard computers then i suggest you to come on to battle net. As for the strategy guide I dont really think its worth it as its now outdated. A better place to learn about strategy and unit is this:
http://wiki.teamliquid.net/starcraft2/Strategyanother good source of information is a guy named Day(9) (recently listed in Forbes Top 30 at 30). He is a player but is more known for his show which he goes over things from basics to extremely advance plays.
http://blip.tv/day9tv/day-9-daily-184-newbie-tuesday-1-4171700Also if you are afraid of devoting time into this game, Brood wars is finally considered dying out this last year, so that means it took about 14 years for it to die.
Things to know when you play online:
when you first play online, you will go through a series of placement matches where the game figures out your skill level. After that you will be placed in a league (from lowest to highest: bronze,silver,gold,platinum,diamond,masters,grandmaster)
If you win or lose a game, i suggest of making a habit of watching the replay of the game (sc2 has a very good built in replay system) to see where you can improve. Doing this will will help you improve your own builds and then help you recognize enemy builds which would allow you to more properly fight them.
Some basic tips of things you can practice from the get go:a.Learn hot keys, saves you time, makes you faster
b.You will come across the word micro and macro alot. Micro means you carefully maneuver your guys so that they could do the maximum amount of damage. Macro means constantly using your money either on more structures or units.
c. try to keep a steady production of workers ( by the end of the game you should have about 75 workers)
d. have fun
You can watch pro matches right now but you will be confused by their extremely fast play style. So i say you hold it off until you start playing online alot. Feel free to ask me questions and if you play on the North american server im always interested in playing.
sorry i didnt read the year on this post didnt mean to dig up old threads