I'll post a little to try and help.
You start out sorrounded by either empty territories or neutral territories. Hovering your mouse over any unit, yours or an enemies, it will show the info for that unit.
Clicking on a unit you control brings up a menu that lets you move the unit (into an emtpy territory or a territory you controll), attack a territory (enemy controlled), bombard (if the unit has long range attack capability), load/unload(only for transport units), amphibious attack(ony for transport units), decomission (removes unit from the game-to help lessen maintenance costs), skip (unit does nothing the rest of this turn), undo, and close(to close the menu).
Move your units into empty territories to gain their value and increase your budget and buy more trrops. Neutral territories usually have more units than you to begin with, but wont attack, so arent a threat. Wait unitl you can take them out comfortably before attacking them.
To buy units click on the dollar sign in the top menu. You can filter whats available to buy between all, land units, air units, sea units, buildings, and technology. You must place units bought at a factory complex. You can place buildings in basically any territory you own. Sea units must be placed in a sea zone adjacent to a factory complex.
Transporting is a little different. Instead of moving the unit to be loaded onto the transort........instead you tell the transport to load,...then choose the unit to be loaded from a list of all units available to be loaded. To unload units you have to chose amphibious assault, even to unload into a friendly territory. Click on the transport,.choose amphibious assault, choose the trritory to unload into, then choose the units to unload.
All of the buttons have tooltips that help explain things which should be helpful also.
Hopefully that will get you started. I may add more about combat later, but thats enough typing for now.
Good Luck.
EDIT- Well, hopefully the guide that Tim mentions will be a little better than mine
