I've been looking for ages but I can't seem to find which css class I can edit to get rid of the gap between the menu at the top, and the first block? (theres an example image below)
http://img166.imageshack.us/img166/8463/gaphq8.jpg
Thanks :)

Try .mainTableCellLeft padding and also look at ...Centre and ...Right if you wish to move other parts of the page up.
HTH