Most of the symbols represent the freedom of thought and choice to do what one wants when one wants--for example, the diary Winston purchases and writes in just out of the view of the telescreen, and then hides each time he leaves the apartment. In it, he writes about how he hates Big Brother (another symbol--since he is not a true person...just a figure head of the society).
"The Bells of St. Clements" and the paperweight Winston purchases in the black market are also symbols of this freedom...a time in the past when people could do nothing or everything as they chose to. Of course, the paperweight also symbolizes the love affair Winston has with Julia--it's transparent, beautiful, and fragile just like their relationship. The coral center represents their love, but since it is easily seen, it also represents the fact that they have been observed the entire time of their trist even if they didn't realize it entirely.
The Prole Woman and her song is also a symbol of freedom and a time that has been which Winston hopes will come again.
There is also the Chestnut Tree Cafe. A place that Winston sees as an area to exchange ideas, but turns out to be more of a "holding cell" for the doomed. The three conspirators drink and eat there until they finally disappear forever, and this is where Winston basically lives at the end of the book.