Just placing a link where you can find lots of information in general about the game:
http://www.uesp.net/wiki/Oblivion:Creatures .Long live wikipedia...
As far as ogres go it doesn't mention any weaknesses.Try ranged attacks though since it is one powerfull beast to face up close and personal.If you have no skills in ranged attack you will need a good mellee weapon. Ogres are quite vulnerable to fire...as most things are...If your char. is no wizzard or battlemage then try buying fire spells, getting a good weapon (fire enchanted ?) and have lots of potions. The ability to get a sneak hit on it (multiplies the damage done on it depending on type of weapon) is also quite usefull.
If all these don't help my advise is to stay clear of them untill you level up more, have better equipment and are ready to face them.
Cheers....