You can access the sql statement of an oracle report a few different ways.
1) Expand the Report tree, Expand Data Model, Expand Queries, Double click the query you need to work with, and in the Property Palette double click the SQL Query Statement. This will open a query window.
2) Right click on the report at the top of the tree, choose Report Editor, and double click the top Node (blue box) which is the graphical representation of the SQL query.
HIH
Attached is a picture of what it will look like.