Really stupid question for a new mac user

Ok so here it goes.

I presently brought all my pictures from my camera in through IPHOTO.

I am now using a trial version of APERTURE, which imported the pictures for me (GREAT!).

Here's my question. Does anyone know where the pictures are stored? I can't stand the file system. I just want to take a picture and upload it to flicker, but i can't. Not unless i resave a picture as a jpeg to the desktop. There must be a different way. When i open up the library through the flicker site it doesn't let me view the pictures, and it is not highlighted so i can't access it. It's been frustrating me. I like to have organization. I like when i open aperture all my pictures are there by folder by date...I love that that's exactly how i want to see my pictures. However, where are these folders saved? Since they were imported from IPHOTO

I'm sorry for the crazy questions. As i said i'm new to MAC...i LOVE IT.. just need to figure out these little odds and ends to work.

Once i can figure out this file structure, i can decide which photo program i am going to buy for work flow...The file structure will made a huge difference for me.

I will buy NX to do my conversions...as i did with windows, now that i know it's compatible with Mac as well

Sorry for the uneducated question.......But thanks for those who offer me help

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Lights, Camera, Action
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