Hello, I recently got back into weightlifting (though I have always been a novice). And I have noticed that my left side (chest, arms etc..) is slightly bigger and stronger than my right. How can I even out my body? I have an O.Bench, (with like 300lb O. weight set) uneven bar and few dumb bells. What exercises or methods would you all recommend?

Everyone has some imbalance from one side to the other, some more than others. It is mostly genetic or due to birth defects or other disease, sickness or nutritional deficiencies at critical growth times. The only solution is to build overall muscle mass. The imbalance will grow less noticable as you increase overall muscle mass.
Some people try to do a few extra one armed exercises for the smaller side, but that may actually make it worse. Arthur Jones (the inventor of Nautilus) used to say that by doing one armed exercises you were more likely to over train the smaller side and it would actually get even smaller.

sorry bud ... your screwed ... working out will only increase the imbalance ... it's in your genes and you will always look funny.

... j/k ... can you tell i'm procrastinating from work?

heh, thanks I guess its a comfort knowing that it'll fix itself so long as I keep lifting.

Replicant, right for your chest this is best. Instead of doing bar presses, use dumbells, Use the same weight for at least 6 months. This means both sides of ur body have to heave their own weight and cannot help each other, it also means that eventually even tho ur left side will find it easier ur right side will find it harder until it eventually catches up to the level of ur left side.

And for arms, thats easy too, dont work ur left arm! doing bicep curls etc just use ur right until it reaches the size of ur left. Its the only way :] its common sense really!

If you wish to still use the bar DONT, but if ur insistant, you can hold the bar in a way were ur left arm holds the bar normally, and right does a wider grip that will work the right side of the chest more. Obviously if u do this ur gonna have to lower the weight a little. But i reccommend the DB tip I gave at 1st.

if you use a wider grip with your right hand, your right pec may get stronger faster than the left, however, then you are going to have an imbalance between your right tricep and your left tricep (your left tri will get stronger faster than your right).

i also have to agree with dswithers that overtraining is a concern when trying to work one side more than the other side...

How much bigger is the left arm? if its about 1/2 inch and below don't worry about it.