Horde:
Shaman: A shammy is determained by what type of spec ur gonna go for, if u want elementalist, your gonna wanna be an Orc due to their high intellect and stamina. If you want to be restoration I would also pick an orc if I were you for the same reasons as being an elementalist. If you were to be enhancement, however, you would probably want to go Tauren due to their having good melee damage, and high life.
Rogue: You would probably want to go Troll due to their high agility, but if you were planning on pvping a lot in the future, I'd suggest undead instead due to their fear ward.
Hunter: I would choose a Blood Elf due to their having high intellect and agility
Lock: I would go Blood Elf due to their high intellect
Alliance:
Shaman: You have to go Draenei, it's your only choice..
Rogue: Go night elf, they have a higher dodge rating than the other classes, and higher agility
Hunter: Go night elf, they have dramatically higher agility than the other classes, and still have enough intellect to be worthwhile
Lock: Go gnome, they have lots of intellect, and a (i believe its 10%) racial talent that can definatly help at higher lvls
Bonus Question Answer: Engineering does suck for cash. If you are looking for money, go herbs/mining and sell wahtever you happen to pick up. Engineering has fun gadgets that can be used for random things. It has repair bots taht are useful, but are becoming a bit more obsolete since burning crusade due to blizzard adding in vendors who will repair for you mid-instance. Lastly, rogues and hunters make decent engineers if you insist you want to be one because they can make jumper cables which can be used to possibly rez the group if you manage to pull off a feign death or vanish during a wipe.